8 series which is better 840 or 850..... for reliability

[XAlt]

I know one sign of guide failure is bits in the oil. Is there a way to inspect via something else? Maybe valve cover removal? At 100k, the covers probably need a refresh anyway. Let's peak inside for an inspection?

Drop the pan and look for plastic. You can poke the lower u-guide (the one that replaced an idler sprocket...) if you dare as well.

Well, I can feed you some more baloney if you must!!
I (not the dealer or an Indy tech) maintained an M62B44 for 17 years from NEW in an 1998, 740 for 178k miles with Oil changes religiously every 3k miles with Mobil 1.
I can attest the maintenance on these engines is simply horrible.

There's quite a few still on the road, but what sends them to the yard 9\10 is either failure of the 5HP24 or the chain guides. The TU engine is even worse when it comes to reliability, but somehow I've managed to shoestring mine along.

In the past 20k for a total of 148k miles.
- VCG and Timing Cover Gasket (probably reused during PO's guide job)
- Oil Pan Gasket
- CCV
- VANOS makes a dieseling noise, I love it but some people get embarrassed easily.

Some people have great luck with it, others don't, it still doesn't excuse a poor design.

[Alec Cartio]

Well, I can feed you some more baloney if you must!! I (not the dealer or an Indy tech) maintained an M62B54 for 17 years from NEW in an 1998, 740 for 178k miles with Oil changes religiously every 3k miles with Mobil 1. I can attest the maintenance on these engines is simply horrible. Oil, intake and coolant leaks are the most common issue. From all that were sold I doubt that there are even a hand full at 20 years as they are simply too expensive to maintain!!! Engine only Maintenance: Valve cover gaskets: 3 Intake manifold gaskets: 4 Crankcase pressure reg: 3 Upper cam-case gaskets: 2 Coolant crossover tubes: 1 Cam position sensor: 3 SHOW STOPPERS!! Cam chain Guides: 1 Coolant pumps: 6 Other general vehicle maintenance like coolant reservoir (4), coolant hoses(many), radiators(3), O2 sensors(4), trans(1) etc. on the 740 is also horrible as well with with too many to list and I tended to replace some stuff wholesale with mileage after 80k miles. Car looked and drove like new when I gave it to my son due to the hoards of parts I kept putting in the car and thing have not changed. No I was not being a mean father, as he was a BMW Master Tech and knew what he was in for!!

What he said ^

The M62 is an overrated nightmare engine. If anything, the M60 with all its sluggishness never had any issues. I only did regular service including one transmission service. Otherwise, nothing else. But the M62, don't get me started. Avus Autosport, F1 motorsports and Empowercars all have copies of my receipts.

[XAlt]

What he said ^

The M62 is an overrated nightmare engine. If anything, the M60 with all its sluggishness never had any issues. I only did regular service including one transmission service. Otherwise, nothing else. But the M62, don't get me started. Avus Autosport, F1 motorsports and Empowercars all have copies of my receipts.

The issue with the 62 boils down to the timing gear. Both leak oil, both have meh cooling systems, M60 has an even crappier OSV, but because of the bulletproof valvetrain the M60 is an engine you can depend on like the Mercedes M119 while the 62 isn't. You still had very bad luck with the 4.4.

plus 5HP30 in the 96>>>>>>>>>>>>>5HP24

[tvjake2]

Well, I can feed you some more baloney if you must!!
I (not the dealer or an Indy tech) maintained an M62B54 for 17 years from NEW in an 1998, 740 for 178k miles with Oil changes religiously every 3k miles with Mobil 1.
I can attest the maintenance on these engines is simply horrible.
Oil, intake and coolant leaks are the most common issue. From all that were sold I doubt that there are even a hand full at 20 years as they are simply too expensive to maintain!!!
Engine only Maintenance:
Valve cover gaskets: 3
Intake manifold gaskets: 4
Crankcase pressure reg: 3
Upper cam-case gaskets: 2
Coolant crossover tubes: 1
Cam position sensor: 3

SHOW STOPPERS!!
Cam chain Guides: 1
Coolant pumps: 6

Other general vehicle maintenance like coolant reservoir (4), coolant hoses(many), radiators(3), O2 sensors(4), trans(1) etc. on the 740 is also horrible as well with with too many to list and I tended to replace some stuff wholesale with mileage after 80k miles.
Car looked and drove like new when I gave it to my son due to the hoards of parts I kept putting in the car and thing have not changed. No I was not being a mean father, as he was a BMW Master Tech and knew what he was in for!!

Ok, so that's one reported chain guide problem on a 740. I'm still waiting to hear of E31's with the problem.

[toomanyparts]

The issue with the 62 boils down to the timing gear. Both leak oil, both have meh cooling systems, M60 has an even crappier OSV, but because of the bulletproof valvetrain the M60 is an engine you can depend on like the Mercedes M119 while the 62 isn't. You still had very bad luck with the 4.4.

plus 5HP30 in the 96>>>>>>>>>>>>>5HP24

My 6/96 production (97 MY) has a 5hp30.

I wonder how many folks bothered to do the most obvious maintenance item and REPLACE the chain tensioner?

Also, no one is bothering to mention the oil pump bolts that back themselves out, which most definitely affected M60s.

[XAlt]

My 6/96 production (97 MY) has a 5hp30.

I wonder how many folks bothered to do the most obvious maintenance item and REPLACE the chain tensioner?

Also, no one is bothering to mention the oil pump bolts that back themselves out, which most definitely affected M60s.

Which affects many engine designs, M70, M5x, etc. M62B44s suffer as well. There's also the valley pan that's almost exclusively a 62 issue (they used foamy crap on the first batches and then moved to the famous leaky gasket + plastic cover combo). 1/97 is the cutoff for the 5HP30.

It's been proven that the new long-spring tensioner doesn't really do much to prevent failure either.

[Timm]

Cor Blimey! One minute this is the E31 community - the next it's a bun fight!

The O/P is well gone and we're looking like a bunch of school kids arguing about who's got the ugliest dad - give it a rest!

[cartoonz]

Cor Blimey! One minute this is the E31 community - the next it's a bun fight!

The O/P is well gone and we're looking like a bunch of school kids arguing about who's got the ugliest dad - give it a rest!

Thank You

[Alec Cartio]

Thank You

Original post went and bought an Audi instead. Hahaha

[72tpik5]

He made the right choice for him, as clearly he was not smitten enough. If you love the car, fixing the issues (that any 8 series brings to the table) is part of the enjoyment of ownership. You don't really know your car until you take it apart.

[TedBobo]

He made the right choice for him, as clearly he was not smitten enough. If you love the car, fixing the issues (that any 8 series brings to the table) is part of the enjoyment of ownership. You don't really know your car until you take it apart.

True that!