The 2001 BMW X5
Some content for this article has been borrowed from various internet sources, some with attribution, some without, and I apologize for this in advance. If you are looking for an X5 full service manual, one is available from Bentley Publishers. I recommend you acquaint yourself with all TSBs, assess whether they apply to your particular vehicle and participate in BMW Forum discussions. A lot of the information contained herein may also relate to other BMW models having the same or similar systems, although access to these systems may be more or less restricted than in the X5. Many routine maintenance items are relatively easy DIY tasks. Others require specialized knowledge, proprietary tools and/or a lift. My particular X5 is a North American model (Left Hand Drive). Some design changes were made as the model matured, so make sure you have current information on your specific model. Exploded parts listings are available on www.realoem.com and some good DIY tech info is available at www.pelicanparts.com and www.fcpeuro.com
By Gary R VanRemortel firstname.lastname@example.org Revision B dated 08/05/14
Engine Type: M62TUB44 4.4L (4398cc [268 CID]) DOHC aluminum alloy 32-valve 90° V8
Avg Fuel Economy: 18 mpg
Bore/Stroke/Compression: 92mm / 82.7mm / 10:1
Warm Idle: 680 rpm
Max Power/Torque: 282 hp SAE @ 5400 rpm / 324 lb-ft SAE @ 3600 rpm
Wheelbase/Width/Track/Length/Height: 111” / 73.7” / 61.4” / 184” / 67.2”
Minimum Turning Radius: 19.85 ft
Curb/Gross Weight: 4795 lb / 6005 lb
Acceleration (0 to 60 mph): 7.6 sec
Coefficient of Drag: 0.36
Roof Load Capacity: 220 lb
Towing Capacity (braked): 6000 lb
Spark Plugs/Gap/Socket Size/Torque: NGK BKR6EIX / .040” / 5/8” / 18 lb-ft
Coolant/DI Water 50/50: 12.7 qt BMW Blue -35 to 265°F
Fuel Capacity/Rail Pressure (at idle): 24.6gal / 42 psig
Differential Fluid: 75W-90 Redline Synthetic
Transfer Case Fluid: 0.5 qt Dexron III
Power Steering Hydraulic Fluid: Pentosin CHF11S
Brakes Front/Rear: 332 X 30mm vented slotted and drilled disc / 324 X 12mm disc
Brake Fluid: Ate DOT4
Battery: BMW/Exide 61217586962 720CCA
Tires (4): 255/55R18H (34 psig)
Lug Nut Bolt Circle/Thread/Torque: 5 Lugs on 4.72” [120mm] centers / M14-1.5 / 103 lb-ft
The BMW X5 is a superb road vehicle, but it is not a full-up off-road 4-wheeler. It is built like a tank and as such, the vehicle is quite heavy. But it is still a car, not a truck. The doors are stout, open up at a good angle and will hurt if they trap any body parts during closure.
The X5 offers exceptional comfort over a long day’s drive and can carry camping supplies and a couple of kayaks up top to boot. It is arguably one of the finest driving sport utility vehicles in the world. A Class III hitch receiver is an easy DIY installation and enables you to haul all of your holiday toys. I strongly encourage all X5 owners to take a personal interest in learning about their car’s systems, care about their ongoing condition and see to their periodic needs. Remember to keep all automotive tools and chemicals locked up or out of the reach of children and pets.
These cars are well designed and I feel that each owner will want to keep it in as good a condition as possible, for as long as possible. Be aware that repair shops may have policies against installing non‑BMW branded replacement parts, so you may be on your own when installing aftermarket parts. Maintenance technicians are not engineers, are not equipped to render a judgment on the quality of your alien parts and they don’t want you suing them if something goes wrong with your car as a result. You should respect this mindset.
If you believe that an important issue has been overlooked or an error made in this article, please contact me directly.
The M62TUB44open deck (it has a valley pan tucked under the intake manifold) V8 engine is naturally aspirated, has 5 main bearings and is strong running all the way to its 6000 rpm redline. The thrust bearing is in the center. Variable intake cam phasing (VANOS) over a range of 20 degrees provides responsiveness with good fuel economy across a wide range of driving conditions.
Most of the little things that go wrong with the M62 engines are relatively easy DIY endeavors. Attention to these concerns will ensure that you get good service from this engine. Some engines suffer from eroding cylinder lining (due to the high sulfur allowed in fuel at the time, combined with excess moisture brought on by short trips). After I bought mine as a CPO in 2004 with 38K mi on the odometer, I later found out that it was originally leased by a real estate agent who made lots of short trips around town showing homes. Brake pads/rotors and a weak rear door locking solenoid were the only jobs on my punch list at the time of purchase. Very few other significant problems were experienced over the ensuing years, but at 130K mi the dealership noticed cylinder 8 to be low during a compression test. Despite ignoring this, the engine still runs strong today at 218K mi and burns no oil. I have always used synthetic oil (at first Castrol and now Pennzoil) and a new filter every 5K mi. After sitting for long periods there is a tendency for cold starts to be accompanied with a second or so of clatter from the VANOS seals leaking down. This seems to be a normal but benign condition as these engines age but, if anyone knows an easy fix for it, I would certainly like to know.
The M62TUB44 uses three simplex chains (one very long and two short) to drive the camshafts and has an externally replaceable timing chain tensioner on the outside of Bank 1. The original chain tensioner doesn’t have enough travel and should be replaced immediately with the new improved (longer internal spring) part. The plastic guides for the primary long chain can breakup under some conditions and if you pull the oil pan and find plastic pieces, you will certainly need to replace one or more parts inside the timing cover. Shimmed for life inverted bucket lifters are used and the compression ratio is 10:1. BMW specifies the use of Premium unleaded fuel although I have always used mid-grade.
Leaking valve cover gaskets can be a problem with these engines. Replacement of the gaskets is an easy DIY job, but does take a few hours of your time and first requires removal of the induction piping and the coil harness boxes. You need to be able to pull the valve covers straight out from the heads a distance of about 2 inches without obstruction. The driver’s side can be especially challenging with the proximity of heater coolant valve hoses compromising things, meaning there is just barely enough room to do the job. Tacking the gaskets to the valve covers first is very beneficial. The process is well articulated in the online forums.
The valley pan on an open deck V8 covers the central coolant channel in the block. The above photo shows the M62 engine with the valley pan removed. The OEM valley pan has an integral elastomeric seal that degrades due to heat after about 150K mi and will manifest as a slow coolant leak out of the top rear of the engine block, dripping coolant down the front of the bell housing. Valley pan replacement is a time consuming job, but not a difficult one, so don’t let anyone scare you out of it, provided you have good mechanical skills. It is an all-day DIY enterprise with you crawling all over the engine and more than a few expletives will escape your lips before the job is complete, but you will save yourself over a thousand dollars since the parts are cheap. If you are doing the valley pan job, do the PCV and cyclone separator system refurbishments at the same time. Study the exploded views of this area prior to ordering parts so that you get all of the items you will need. I won’t say that the design of the M62 Positive Crankcase Ventilation system is poor, but it has a propensity for cheesing up and, when (not if) it happens, you will start to see blue smoke periodically from the tailpipes as crankcase oil burps up into the intake. All of the red silicone gaskets can probably be reused, but all of the other o‑rings and seals should really be replaced.
Ignition is via the Bosch ME 7.2 electronic management system. Individual coil packs sit atop each spark plug, each retained by two M6 studs and nuts. Per BMW, Bank 1 (passenger’s side) cylinder designations front to back are 1, 2, 3 and 4, Bank 2 (driver’s side) are designated 5, 6, 7 and 8. Firing order is 1‑5‑4-8-6-3-7-2. Spark plugs in this high energy system should be replaced every 50K mi and robust electrode types should be used. Changing plugs is an easy DIY job, taking about an hour. Be careful when tightening the nuts and bolts, as threads are easily stripped in the soft aluminum/magnesium castings if over torqued.
These engines require 8 qt of the finest Synthetic 5W-30 or 5W-40 oil you can get your hands on. I use Pennzoil Ultra (SOPUS) but their Euro stuff is also great. Their new PurePlus is probably the best oil you can currently buy. Establish regular oil/filter service at 5K to 7.5K mi intervals, any other practice of further extending service intervals being false economy. I recommend Mahle OC602 and Mann W719/7 oil filters. I feel that the cheapest oil filters having common paper media are virtually useless at trapping combustion by‑products (mostly carbon) that get into the oil. An oil change is also an easy DIY job, taking about 30 minutes. I always install Fumoto oil drain valves on my vehicles to make my oil changes easier. Due to the way the M12-1.5 drain plug is angled and recessed on the M62 engine oil pan, their F109 or F109S valves require an ADP-109 extension. Never let the oil level get low — if the low oil light comes ON, it may be too late.
The OEM dipstick has a plastic handle and end made of reddish plastic that makes it difficult to discern the oil level, since oil turns brown in short order. BMW engineers who thought this was a good color for a dipstick end should be fired. I bought a new dipstick and coated the plastic end with white 2-part epoxy ink from the printing shop. Now it is quite a simple task to read the dipstick.
The coolant used is BMW blue ethylene glycol and it is likely incompatible with OAT mixtures (they can combine to form an insoluble gel). The additive package in all coolant depletes slowly over heat cycles, so change it out every 50K mi or 3 yrs, whichever comes first. Pressure testing the cooling system at the same time is always a good idea. Pressure flushing and flow checking should be done at 100K mi with a new radiator being due somewhere between 100K and 150K mi. My OEM plastic coolant expansion tank split before making it to 100K mi. I bought the whole thing with cap and sender online for around $140.
The coolant pump is well made, lasts for ~100K mi and changing it is an easy DIY job, taking about an hour and a half. Visually check for coolant seepage at the sealed bearings, evident by coolant seeping out of the weep hole on the underside of the housing halfway between the rear bearing and the front bearing. Check for gasket failure, evident by a greasy looking dirt buildup on the engine block right under the pump (because boiled out glycol becomes sticky). Proper torquing of the pump attachment bolts is critical to a good installation. Change the two serpentine belts and the thermostat at the same time as the pump.
Any and all plastic parts within the engine bay should be inspected closely to ensure that they are in good condition for continued use. BMW uses far too much plastic in the cooling system than I think wise. If you are accustomed to just dropping the rather heavy hood and/or your gas struts are weak, you will eventually break the top portion of the vertical radiator baffles that seal with the hood. These are cheap and easy to replace, but require front bumper removal and two hours of your time to do so. Make sure that you cut open the bottom relief flaps. Thermostat replacement is also an easy DIY job, taking about an hour.
The coolant level should never be allowed to get low in the expansion tank, and if the low coolant idiot light ever comes ON, it’s likely too late. The float indicator is prone to crystalizing and breaking off and, if you don’t replace the expansion tank proactively, you may find your indicator floating loose in the tank. The frailty of the rigidly mounted cantilevered plastic expansion tank was not well thought out for use on an SUV. After the original one cracked, I put some rubber grommets on the attachment bolts of the new one to allow a greater range of motion off-road and haven’t had the mounts break a second time.
BMW uses crimp-on hose clamps that can sometimes lose tension and blow off. They should be replaced well before reaching 100K mi, along with the hoses they retain. For most 1” ID and smaller cooling applications calling for straight or gently curving hose, I prefer fiber reinforced silicone hose often used on Police cars. I have used HPS, Verocious and Silicone Intakes hose firewall forward with good results on both cars and airplanes.
There is a hard plastic burp line (find #8 in the above line drawing) running from the rear fitting of the expansion tank to a hose going to the driver’s side radiator end cap. It has a tendency to overheat and shatter, so mine is now a length of hard aluminum line with crimp-type clamps on the hoses.
Modern aluminum radiator cores with rubber gasketed crimped on plastic end caps last between 100K and 150K mi (the plastic end caps begin to crystalize with accumulated heat cycles and erode first near the top hose port). Radiator replacement is an easy DIY job taking about two hours, but you also need to remove the engine fan that requires special tools. The radiator drain-plug is a blue plastic item located at the bottom of the left radiator end cap facing down and is a bit fiddly. It has a rubber seal under the head and a barb on the end to retain it in the port when unscrewed. Be careful not to over tighten it or you may develop slow seepage that might not show up on the ground.
Serpentine Belts and Fans
This engine uses one seven rib 7PK1635 for the main belt and one 5 rib 5PK1030 for the air conditioner compressor. They generally last for somewhere between 50K and 100K mi (about 5 yrs). The tension on the belts is retained using spring loaded tensioners. The belt tensioner and idler pulley bearings are probably good for 200K mi or more. Replacement of the belts and associated parts is an easy DIY job and takes less than an hour. There is an engine mounted fan (with viscous clutch) behind the radiator and a supplementary electric fan out front. The electrical fan is enabled by a coolant temperature sensor via the ECM. The mechanical fan clutch will last maybe 150K mi and is an easy DIY replacement, if you have the special BMW tools. The clutch attachment to the engine pulley is via a left handed thread (so in this case, righty loosey). The new fan differs from the original fan, in that the new ones have a perimeter ring which improves air volume molded onto the blades.
The X5 induction system begins with a scoop above the radiator feeding directly into the filter box, thru a short coupler that incorporates the MAF sensor mount, then into a short plastic induction pipe to the front mounted throttle body.
Reusable air filters like the K&N are available to replace disposable paper media filters and there are several aftermarket Cold Air Intake kits that may prove to be slight improvements over the OEM design.
If your air filter is working well, you will only need to clean your MAF sensor every 100K mi or so using a commercial MAF sensor cleaning solvent. If you have access to the right tool bit for the security screws, the MAF sensor can be unplugged and removed from the intake pipe for easy cleaning access. I replaced my security screws with common head types.
Filter-Return Type Fuel System
A vane pump with integral float sender and particulate filter sock sits in the tank. All submerged fuel pumps rely on the fuel in the tank for effective cooling, so don’t make a habit of running the tank near empty. Conversely do not overfill the tank or you may foul the vapor canister system. The fuel supply is a filter-return type system, meaning the hot fuel from the injector rail is not returned to the tank, fuel line routing is simpler and there are fewer opportunities for leaks. Any time you shut down a highly heat soaked engine and start it up again before it has had sufficient time to cool, vapor could have already formed in the rail. Winter blend or fuels of poor quality may have some influence on this tendency. All of that heat energy that used to get carried into the fuel tank in a return line system now just gets to boil the light ends of trapped gasoline in the rail at startup. All fuel systems have advantages and disadvantages, so just be advised of this particular system’s characteristics. If you get a lazy fuel injector, your engine may start but idle poorly until the fuel flow stabilizes. It probably also means it’s time to send the injectors out for cleaning and flow balancing.
When things go wrong in this simple feedback network, it can be difficult to determine precisely which component is actually at fault without specialized diagnostic equipment. It’s like a series string of Christmas lights. It could be a sensor, an injector, the fuel filter, F47 (fuse), K96 (relay) or the fuel pump.
The rather large inline fuel filter, Mahle KL96 or Mann WK532, has three ports (inlet, outlet and return), an end mounted pressure regulator and is located behind the splash panel just in front of the fuel tank on the left side. It should be replaced at least every 50K mi, but some say sooner, especially for those that recirculate fuel back to the tank as in the X5. Pull the fuel pump relay K96 or fuse F47 (25A) both located in the area above the glove box (you need to remove the plug-in flashlight and pull forward and down on two tabs provided on the ceiling of the glove box), run the engine until it dies to reduce the rail pressure and then remove the splash panel to access the filter. There are many screws holding this panel on (some of them well hidden). Once you locate the filter you want to squeeze the hose to the engine (the one going to the end of the filter having a single nipple) with a pinch-off tool or a cup of fuel may spit out once disconnected from the filter. Be prepared to make the filter exchange rather quickly. If you are doing the first filter change, you will need to cut off the three original crimp clamps and replace with screw types.
On the way to If you ever need to remove the fuel rail you will find that the engineers at BMW who designed the boxes for the injector and coil wiring did the DIY crowd no favors. These wiring harnesses are tightly tucked into two long plastic housings and you will need to get the housing lids off to access the plastic barbs that release the injector connectors. I cut about half of these plastic retention features off so that the lids can be more easily removed. I did the same at the bottom, so the injector connectors can be readily extended for easy mating and unmating individually. The fuel rail itself is a U-shaped pipe and there is a Schrader valve on the front crossover. Disconnect the vacuum line and connectors on the sensors then remove the 8 clips holding the rail to the injectors. Remove the injectors one at a time and mark them with cylinder numbers for reference. The removal of the rail from the supply line requires a special tool (Performance Tool W83152) to release the quick disconnect fitting.
These Bosch fuel injectors are pretty easy to keep clean, as they are not the high efficiency type. Fuel injector cleaning solvents used in the fuel tank are quite effective in keeping the orifices and pintles in these particular injectors from accumulating varnish and gumming up. There are a number of DIY on‑car solvent flushing systems (OTC 7448 and others) available for between $120 and $220, or you can build your own for less than half that. Off‑car cleaning is much more effective than forward flushing of the fuel rail and the injectors in‑situ, since you can then clean/replace the inlet screens, back-flush, verify the spray pattern and confirm flow matching on an individual basis. Flush the rail with Berryman’s B-12 while you have it off.
If you suspect you are having individual injector firing issues, a Noid light (Lisle 27800) or current limited LED can confirm in a flash that a turn-on pulse is being received from the ECM with the engine running. If you get good pulses, then the problem is likely with the injector(s). Another not so trusted method is to hold a long bladed screwdriver up against the operating injector body and the handle to your ear as though it were a stethoscope.
If you are cleaning your own injectors, keep the misting of volatile solvents contained, ground all static sources, keep sparks away, use a safe/low turn on voltage and keep the duty cycle lower than 80% to avoid overheating the coils. Keep in mind that when the injector shuts off, the back EMF from the collapsing flux field will produce a sharp spike, so always connect a back biased diode such as 1N4005 in parallel with the injector in any switched circuit as a discharge path. Replace all o‑rings, lubing them with a little engine oil. Reseat them individually into the rail and reinstall the retention clips before attaching the fuel rail and final leak testing.
There are also many good injector cleaning services out there using the ASNU or similar bench flow matching systems. WitchHunter, LinderTech, AUS Injector and Injector-Rehab all do good work.
Throttle Pedal and Throttle Body
The throttle pedal sender and throttle body are pretty straightforward and trouble-free. The ECM automatically adjusts for TPS position, so virtually all that needs to be done is to keep the throttle butterfly clean using B-12.
ZF 5HP24 (BMW A5S440Z) 5-Speed Automatic Transmission
This 5 speed ZF gear box is pretty solid, is used in many brands of luxury sedans and sports cars and there are a lot of them in service. They have known issues that are well understood, so there should be no surprises after all these years. There is no dipstick, Jimmy. ZF claims this box is filled‑for‑life, but the fluid, filter and pan gasket should really be changed out at least every 100K mi, some say 50K mi because not all of the fluid comes out during draining. Always confirm that you can loosen the fill plug before you remove the drain plug. A little more than half of the total 10.2 qt fluid capacity is accessible during pan drainage (the balance being trapped in the torque converter). The transmission fluid internal filter is widely available. Refilling involves pumping fluid, running the engine, shifting thru the gears, measuring fluid temperature, pumping more fluid, all with the engine running until fluid drips out, then installing the fill plug, all the while working around hot exhaust pipes. ZF specifies Esso LT 71141 fluid for the 5HP24. Folks have used any and all of the following: ZF Lifeguard5, BMW branded fluid and Redline D4. They all seem to work fine.
A weak point in the transmission is with the internal wiring harness where a crimped-in temperature sensor gets flakey over time, leading to erratic operation and un-commanded downshifts at speed. The whole $200 harness needs to be replaced when this occurs, but it is an easy 2 hour job on a lift at the transmission shop.
The NV125 transfer case has a 38% front vs 62% torque split arrangement and is considered a light duty unit. It takes ½ qt of Dexron III fluid.
The steel drivelines have a Guibo (also referred to as a Jurid or Elastomeric Flex Coupling) at their front ends and the rear driveline has a center stabilization bearing for refinement. Guibo replacement needs to be done very carefully to ensure that the critical balancing of the driveline is not disturbed. Always mark all bolt positions, keep them paired up with their specific nuts and don’t allow anything to move until everything is back in their exact original positions. Guibos have directional arrows molded in, so make sure that you study everything before disassembly and that you have it facing the right way during reassembly. Guibos are good for at least 100K mi, unless you’re driving off-road a lot.
There is a known problem with the front drive shaft that BMW so far has failed to acknowledge, since it generally only occurs in vehicles that are long out of warranty. The OEM shaft splines are about 25mm too short. They fail to fully engage the transfer case output gear internal splines, ultimately leading to stripping the shaft splines out and leaving you stranded with a whirring sound emanating from underneath the car. Somewhere around 150K mi this will happen to every all-wheel drive X5s having this drive train. Most of the transmission shops are well aware of the issue and are able to get the WholesaleImportParts.com or CobraTransmission.com aftermarket shafts with 1” longer splines now going for around $600. This is also an easy DIY job taking around an hour, as long as you can get the car up on a lift. Occasionally the transfer case Hy-vo chain will break instead and this is a little more of a problem since you now have to break open the transfer case. Still not the end of the world and probably still could be done as a DIY, but why risk it?
The drain and fill plugs for both the front and rear differentials are readily accessible for drain and fill, although you will need to remove the large aluminum belly plate to gain access to the front differential. I would do the lubrication service on both differentials every 100K mi. Unless you have a special installation, there were no Limited Slip Differentials installed in these vehicles.
The X5 axles are basically torsion rods, so the car continues to rock fore and aft as you come to a spritely braked stop. It still feels strange to me, even after living with the car all these miles. Also the CV joint rubber bellows covers can crack over time and will need to be replaced before bad things happen to the joints. Keeping these well silicone sprayed will help extend their life.
The X5 exhaust system is all stainless steel with double wall tubes. There are two upstream wideband sensors and two downstream conventional lambda (O2) sensors. The lifetime of the heated types is typically at least 100K mi and they normally fail due to catalyst depletion. As they age they tend to report leaner and leaner mixtures, the ECM enriches the long term fuel trim in response, exhaust gases get richer, producing more carbon monoxide and hydrocarbons, leading to poorer fuel economy. Replacing the upstream sensors well before end of life is good practice and probably justifies their cost vs wasted fuel.
Relays are used on some high current circuits to keep switch contacts from having to switch high DC loads that can produce pitting/arcing, but does mean that these circuits become slightly more complex in the process. Having diagrams of the fuse/relay boxes located thruout the car, combined with a listing of which relay and fuse does what, could help out tremendously in a roadside emergency.
I like to make sure the car is unlocked and the keys in my pocket any time I disconnect the battery. DO NOT disconnect the battery and then close the rear gate, as you may find it difficult to get back there to reconnect it.
The OEM battery is a maintenance free unit that usually lasts at least 5 yrs. The internally rectified/regulated alternator is water-cooled.
The molded plastic end retainer tabs on the side marker lights (and other similar polystyrene or polycarbonate lamp fixtures) stress crack over time so, while they are still new, wedge some EPDM sponge rubber between the body and the tab for support and you will extend their life.
The battery in the key remote is automatically charge in the ignition. There are procedures to reset the maintenance interval and reteach your key fob remote posted on the BMW forum.
Just a few words about Euro color coding. Wiring Colors are abbreviated in textual manuals.
|B is Black||G is Green||K is pinK|
|LG is Light Green||N is browN||O is Orange|
|P is Purple||R is Red||S is Slate|
|U is blUe||W is White||Y is Yellow|
A browN wire with a White tracer would be NW.
Black base colored wires indicate ground circuits, the wire connecting an electrical unit to ground, usually the car’s metal chassis. A browN base colored wire is HOT or one that always has power present and is not fused.
Since the browN wires run different circuits, it is necessary to further differentiate them with the tracer color. The tracer is a different colored stripe running the length of the wire to indicate the particular job of that wire. Therefore a browN wire with a Yellow tracer is for the generator warning light while browN with a White tracer is for the ammeter.
BlUe wires are for the headlights, with plain blUe being Power to the dimmer switch, while the Power from the switch is denoted two ways. BlUe/Red (UR) is for the low beams and blUe/White (UW) is for the high beams and the indicator lamp.
White denotes a circuit that is powered when the ignition is ON. A plain white wire runs the fuel pump, ignition relay, and various fuse box connections. White with Red tracer (WR) is the power to the starter solenoid, and White with Green tracer (WG) is power to the radio. White with Black (WB) is power to the ignition coil unless there is a ballast resistor, then the wire is White with Light Green (WLG).
Slate indicates circuits that are hot when the ignition is OFF, such as emission control power. Purple is for always hot circuits with fuses such as courtesy lamps (PW) or key buzzers (PG or PK).
At low speeds the front struts are stiff and produce a somewhat harsh ride over rough road surfaces like brick or cobblestone, but at freeway speeds everything seems just about right for a vehicle this heavy. The front struts are conventional and last over 150K mi. Replacement of the front dampers is an easy DIY job taking about an hour each, as long as you have a spring compressor. The rear suspension has auto-adjust ride height pneumatic bags and the associated compressor is situated under the spare tire. These “springs” last 120K to 150K mi and you will know when the bladders need replacing (they develop small ozone cracks on the outside of the fold), as you will suddenly notice the car sagging to one side in the parking lot after sitting for a few hours. They will continue to pump up when the key is ON, but will continue to leak down while parked. Replacement is a simple DIY job taking about 30 minutes each. If one is leaking, the other one is about to. I coat the bladders of the new bags in the area where they make a fold with DC4 or similar high vacuum silicone grease before installing and this will extend their life substantially. The compressor system is pretty trouble free and is keyed ON and OFF on the road by sensing limit switches. The suspension softens or firms up as road and load conditions warrant. If you don’t like the pneumatic bags, ECS Tuning has standard coil spring replacements at a decent price. Front and rear anti‑roll bars reduce body lean somewhat in turns, but this is still a heavy, relatively tall vehicle and significant lean during cornering is unavoidable. Hub bearings are a robust sealed double cartridge‑type, greased for life and never require repacking. They should last well over 200K mi.
I am a big fan of Powerflex brand urethane bushings when the time comes to replace any of the aging OEM elastomeric bushings used thruout the suspension. Be sure to lube the inside surface of the anti‑roll bar bushings with the included grease or they are guaranteed to squeak. The links that extend from the ends of the anti-roll bars (particularly the front ones) have bearings that will wear out (making a clunking sound when you drive over speed bumps and curbs) sometime after 100K mi but they are an easy DIY job taking about 15 minutes each. The replacement job does require a thin 18mm bicycle cone wrench (Park Tool SCW-18 <$10) to hold the backside of each bearing while you torque each locknut.
The front of the X5 is lower than most sports utility vehicles, but the underbody systems are pretty well protected from road debris by a heavy aluminum skid plate in front that covers the engine area and plastic splash guards elsewhere. I have never experienced any road damage to the X5 underbody parts.
Rack and Pinion Steering
The steering system is a rack and pinion design providing a suitable level of driver feedback, without compromising its luxury-class smoothness and feel. The steering feel is somewhat heavier than in a sedan, but seems about right off-road, where lighter control could snatch the steering wheel right out of your hands. Parking is still relatively easy, but your grandma might have a little trouble maneuvering this large car in close quarters. It has excellent stability at highway speeds, groove wander and tramlining are minimal.
Dynamic Stability Control (DSC) is standard equipment on the X5 and reduces drive torque to the wheels by controlling the throttle position, ignition timing and fuel supply to the cylinders. Wheel spin is detected by the anti-lock brake sensors after comparing information supplied by all four wheel‑speed sensors. The DSC system may be manually canceled by pressing a switch on the center console to power out of deep snow or when using tire chains. Dynamic stability control is active at all speeds to enhance car control in slippery conditions. When wheel spin is detected, the anti-lock electronic control module calculates the engine torque level that can be utilized without causing the tires to slip.
The X5 brakes are quite effective for such a heavy vehicle. It uses the Bosch 5.7 ABS unit in a split front-rear arrangement. I use Drilled and Slotted Centric Power Stop Discs, Centric Semi‑Metallic Pads (virtually no dust, much more bite than OEM pads and their stopping power only improves as they get warm) and Ate DOT4 fluid. I used to use their Superblue Racing Fluid, but as of Aug 2013, it is no longer carried in most US auto parts stores, due to a twenty year old DOT decree that automotive brake fluid be clear or amber in color to avoid confusion when regularly servicing vehicle fluids. Cool Carbon and Akebono pads are also good choices, but may be noisier than the softer pads. The limits on rotor wear are 28.4mm for the front and 10.4mm for the rear. Pad minimum thickness is 3mm. Speedbleeders are available that make single person brake system bleeding much easier. They also sell a tubing equipped plastic recovery bag (like an IV bag) that catches the expelled fluid for easy disposal. BMW specifies the following bleed order: RR, LR, RF and LF.
ABS Control Electronics are in the black box attached to the hydraulic block and can be removed for repair separately from the block. All the connections from the circuit board in the box and the hydraulic block are inductive and the box attaches with six screws. Send bad modules out to ModuleMaster.com for repair. There is some difference of opinion among BMW techs as to which wheel speed sensor is used for the speedometer input and occasionally it is the module itself. The harness connector has a sliding plastic end bar to seat and lock the connector in place and it needs to be drawn out from the end to disconnect the harness.
The X5 wheels are hub-centric yet the lug bolts have conical (not flat) washer bases. OEM wheels are powder coated, so stay looking good without a lot of effort unless you curb them. I use Michelin MXV4 tires because they wear well (I get around 60K mi out of a set) and grip great under all conditions except ice.
It seems to me that BMW could easily have done a better job of either zinc plating or painting the wheel hubs, as they become quite a rusty mess after only a few years of moisture ingress. I hit them with a wire brush and then a light coat of VHT or Rustoleum enamel from a rattle can when doing the first brake job. Put grease on the wheel center boss to keep them from sticking to the painted steel hubs and a drop of oil on all lug bolt threads.
The wipers blades are three different lengths (D=24”, P=22” and R=18”). Recent research has rediscovered that windshield washer fluids not containing sufficient alcohol (Methanol was taken out of many manufacturers’ formulations years ago to render them less toxic to children should they try to drink them) can harbor the Legionella bacteria for many months and it can be spread when the mixture aerosolizes during use. I’ve always added 3 cups or so of denatured alcohol (you can use isopropyl instead if you prefer) per gallon to washer fluids to better cut road grime and render it resistant to freezing during winter. This practice also makes washer fluid unable to support bacteria growth (sailors used to drink beer or watered down rum with lime juice because straight water would quickly go stagnant). You needn’t add lime juice, since windscreens aren’t prone to scurvy.
The window regulators are cable types and last around 100K mi. They are easy to replace. Contrary to the instructions in the Service Manual, you do not need to remove the window trim. You will need to replace the regulator and the plastic clip. Give the window guide tracks a good shot of silicone spray over their entire length before you install the new glass or anytime the raising or lowering of the window seems labored.
The sunroof has drains that pass thru the A pillars and if they get plugged up they can leak water into the interior.
Cabin Seating and Interior
I like dash mats in all of my vehicles and Cover King makes a good one. The pixels in the LCD displays for the instrument panel and the stereo get flakey over time and they can be repaired as good as new relatively cheaply by sending your display modules off to GermanAudioTech on Ebay. The radio is released by removing the volume knob and releasing the hex headed latch in the small hole near the potentiometer shaft. The instrument cluster comes out after removing two top screws. Separate the latching harness connectors from the modules and they’re out.
Since the front doors are so heavy, I have installed non-slid strips on the lower front door panels to protect against shoe marks while unceremoniously kick the doors open. There are two rather fragile spring clips holding the rear cargo area floor down and they are only replaceable at a ridiculously high price.
Extensive safety considerations are engineered into the X5. Many airbags are provided for the driver and passengers, along with front pyrotechnic seat belt pre-tensioners to take up seat-belt slack during impact.
The pollen microfilter is easily accessible at the rear of the engine bay plenum. Twist the two plastic latch fasteners 90° and open the plastic enter panel/door. Pull out the old filter and install the new. Twist the fasteners back to lock.
Keep all hoses, and for that matter all elastomeric (rubber) items (except the serpentine belts), well coated with a good silicone oil spray for longest life. Don’t waste your time and money on silicone sprays sold in most auto parts or hardware stores, as the industrial rated stuff is much better. I recommend using the food grade low viscosity spray CRC 03040 (Fastenal carries it) for large area coverage and Easy Rider RT630A (paint ball aficionados use it) for coating small bushings, because it is thicker and clings better. Dupont makes a Krytox Spray with PTFE for bicyclists that has numerous applications for cars.
The X5 is a great open road car and you want to protect the front end against FOD. Lexan hood bug guards and clear protective bras are available and are highly recommended.
I use Surf City Garage Voodoo Blend Leather Rejuvenator to treat the leather.
Other protectants may be needed in different climates. Noxudol 750 anti-corrosion treatment cavity wax should be applied on and/or into all places you can get to with the included snaky hose that might be subject to moisture ingress and road salt effects. If you can get the car up on a lift, look for lower areas that are prone to moisture or rusting and apply it (just don’t get it on braking surfaces or items that must move freely without binding).
For treating the fuel injection system I prefer B-12 Chemtool, but Valvoline Syn-Power VPS and BG 44K are also good choices.
The best plastic treatment I’ve found is Meguiar’s Ultimate Protectant (more water resistant than Armorall).
My X5 has the OEM Halogen headlamps and they are quite satisfactory as is. The headlamp lenses are plastic and, as a result, prone to UV crazing. A good whitening toothpaste buff can bring these back to a gloss.
Halogen lamps are available in various enhanced performance versions and should always be used in pairs so that the color and intensity of the beams on one side of the car are substantially similar to the other side. All other lamps are available in Long Life or LED equivalents. It’s a personal thing, but frankly, I find LEDs used in brake light applications really irritating, because they come on so abruptly, vs incandescents. Replacement lamps are as listed below:
Position Sylvania P/N Description
- Front Lo Beams (2) H7 55W Halogen
- Front Hi Beams (2) 9005 60W Halogen
- Front Parking (2) 3457 LL 8W/28W
- Front Turn Signal (2) 3457 LL 8W/28W
- Front Fog/Driving (2) H3 55W Halogen
- Front Side Marker (2) 2825 LL 5W
- Glove Box (1) 6418 LL 5W
- Interior Dome (2) 6486 5W
- Interior Map (2) 6486 5W
- Door Puddle (4) 6418 LL 5W
- Rear Tail (2) 7528 21W
- Brake (2) 7506 21W
- Rear Turn Signal (2) 7506 21W
- Rear Back Up (2) 7506 21W
- Rear License Plate 6418 LL 5W
- Rear Cargo Area (2) 6486 5W
The OBD2 system is conventional and an appropriate scan tool (I have an Innova 3130) should be used to get an idea of how well all your systems are working. Get a good list of Generic and BMW specific DTCs so that, when your car throws a DTC you don’t recognize, you can at least have a rough idea of what is going on. Some tools are more sophisticated than others and many auto manufacturers are very keen to keep their OBD2 details proprietary. The Autologic, AutoEnginuity and ScanXL tools are high-end tools for professional shops, the Snap-On Ethos is a good mid‑range tool and the Innova Equus series are decent low-end tools for the DIY’er. Scan your car’s systems Key-ON Engine-OFF (KOEO) and read the live data Key-ON Engine-Running (KOER) while driving at varying speeds when things are running good, so that you will be able to recognize normal range readings. The live data can often be captured in memory and subsequently uploaded to your PC to produce graphs and reports. Do not begin replacing things on a single throw of a given DTC, but do use the tool and the OBD2 system to help you to baseline, monitor and troubleshoot your car’s systems to look for trends over time. Try to develop a good diagnostic sense that allows you to proceed logically to narrow down and pinpoint the malfunctioning item in the system. There are a number of YouTube videos that can help you to hone good troubleshooting skills.
As with all systems, their ability to function as designed depends on each component doing its job correctly and consistently. The OBD2 diagnostic capability helps to pinpoint which of the many components is the slacker in any given subsystem and allows you to channel your diagnostic and corrective efforts methodically towards those items most logically responsible for the fault. Like Sherlock Holmes, take your time in sorting thru the evidence and try to eliminate the extraneous to arrive at the truth, but “If it isn’t broke, don’t fix it”.
Following are some of the normal range OBD2 Parameter Identifications (PIDs) accessible by my tool:
Fuel System 1 (KOEO Open Loop, KOER Closed Loop)
Fuel System 2 (KOEO Open Loop, KOER Closed Loop)
Calc Load (KOEO 0% KOER 0 to 100%)
Eng Cool Temp Sensor (-30 to 260°F)
Short Term Fuel Trim B1 (-10 to 10%)
Long Term Fuel Trim B1 (-10 to 10%)
Short Term Fuel Trim B2 (-10 to 10%)
Long Term Fuel Trim B2 (-10 to 10%)
Fuel Press Sensor (40 to 50 psi)
Man Air Press Sensor (0 to 30 inHg)
Engine Speed (0 to 6000 rpm)
Vehicle Speed (0 to 120 mph)
Spark Adv Cyl #1 (0 to 35°)
Intake Air Temp Sensor (0 to 130°F)
Man Air Flow Sensor (0 to 30 lb/min)
Throttle Pos Sensor (0 to 100%)
O2 Sensor B1 S2 (.2 to .8 V) .45 V is ideal
O2 Sensor B2 S2 (.2 to .8 V) .45 V is ideal
Malfunction Indicator Lamp (MIL) ON/OFF
Used X5 Buyer Advice
After reading and understanding all of the information presented in this article, the following items should be included in your condition inspection, plus you should line up a competent BMW mechanic to go over the target vehicle:
- Overall condition and mileage. Does the car look as though it was well cared for? A 10 year old car should have no more than 150K mi to be a good candidate for purchase, unless you have the ability and intention to do ALL of your own repairs.
- Service history and seller evaluation. Look for parts receipts and labor invoices or personal seller mechanical ability (are they knowledgeable about the car’s systems?).
- Engine condition, fluid leaks and noises. Look for all conditions that would indicate neglect or incomplete maintenance. If you can, remove the plug covers and disconnect each coil in turn for a few seconds. Any unusual behavior is cause for concern. Listen for unusual tappet or primary chain noises. Check oil level and condition. Check brake and power Steering fluid condition.
- Engine bay examination. Look for cleanliness and attention to detail. Are all fittings and parts OEM equivalents.
- Coolant System. Look at the fans, radiator fins and hoses for good condition and proper operation. Check coolant color (blue) and level. Try to start the car cold and observe warm-up. It should crank and start readily. Does the engine come up to temperature in ten minutes in the middle of gauge range and stay there? Does the electric fan cycle appropriately between OFF and ON (turn on the AC)? Look for proper engine movement upon a quick stab of the throttle.
- Drivetrain. Look for guibo condition and leaking seals.
- Suspension. Bounce on each of the four corners and observe resistance and rebound authority.
- Steering and Brakes. Look for centering tendency, slop and good braking authority. Look under car in the area of the brakes to ensure that there are no caliper leaks. If you can get each wheel up in turn, check bearing play and smooth rotation.
- Wheels and Tires. Visually evaluate tire type and tread, curb rash and condition.
- Electrical and Lamps. Make sure all systems operate to spec in the day and in the dark. Check charging voltage at battery B+ (it should be about 14VDC).
- Entertainment center and Instruments. Make sure all items operate to spec and radio antenna extends, retracts and stops. Operate all panel and steering stalk functions both sides. Ensure all display pixels on the instrument cluster and radio light up.
- Sun Roof. Cycle the sun roof and observe action. It should operate smoothly.
- Interior and Seats. Inspect for leather condition, seat and driving column position memory.
- Body, Paint and Corrosion. Operate all doors, boot and bonnet and all locks both manual and remotely operated via the key fob. Look for nicks and overall finish condition. Look under car in the area of the wheel hubs to ensure that there are no caliper leaks they are rust free.
- Glass. All windshields will have some degree of pitting but ensure that the rest of the glazing is in good condition. Ensure all windows roll up and down and the rear window heater is functional.
- Plastic examination. Look at all plastic and rubber items in the engine bay and under the car to look for cracks.
- Missing items. Ensure that the cover for the engine firewall plenum is in place.
- Smog reports. Review for trends.
- OBD2 scans. Look at current real time readings at speed.
- Test drive. The engine should idle smoothly and take throttle readily. Steady torque increase should be apparent and the steering should be neutral and not twitchy. At low speed, the suspension should be stiff and at freeway speeds (and up) the car should be well under control regardless of road conditions. Brakes should be strong with no tendency to fade. Shift into manual under a variety of conditions and observe the results. It should retain the gear selected and there should be no back-firing or popping under any conditions.