1995 850ci m73 e31 wishbone control arm bushings.

[sshivaram]

This! If you're on a budget, sell the car until you can afford a better one. Your repairs and "observations" are cringe worthy.

Why sell the car ? If i am on a budget, and not in a rush to get this car on the road, why sell it ? this is a project car for me.

I have it up and running after going through six years of hell. Have to slowly bring it back to glory. Throwing money at one single part without doing it efficiently is not my way of working on the car. I will explore it and do it my way. What makes you cringe and nauseous may be regular surgery for one with experience.

Sounds humorous if you say only those with big budgets should work on an 850ci and get the repairs done by expert mechanics, lmao.

This is a hobby lol.

I absolutely and highly respect members opinions here, and especially thankful to those who have caught my mistakes. Its a learning lesson, to understand and know the difference between a bearing and bushing in this instance. We wouldn't have a technical discussion here if i had just bought an entire arm and replaced it. The upper control arm can live with a new bearing, and its very interesting to explore that !!

Right now, car runs fabulous. I still have plenty to do. Will rake up new threads for them:
1. Left wing was smashed completely when a deer ran into my car. Have to fix this.
2. Sunroof stuck closed and won't budge, and entire headliner needs replacement.
3. Twisted driver seat.
4. Missing sound insulation.
5. Sticky driver side door.

Who the heck will buy this car ? I was offered $500 by someone saying this was a worthless car.

Cheers !

[cartoonz]

Sunil,

Look, while it may seem like some of us are trying to beat you up a little for some of your approaches, there is a bigger picture. You DID use a Grade 8.8 bolt where it calls for a 10.9. That's why people are freaking out, it is unsafe.
Thing is, it may not just be you that gets killed because of some of these mistakes. No, it could be the old lady on the side of the road, your neighbor, or somebody's child.
THAT is why we are telling you NO!

As for Lowes or Home Depot - I would not trust any of their bolts to hold up, no matter what grade they may claim they are... these are mostly complete Chinese crap metal fasteners.

If you want ANY bolt you need, and do not want to pay BMW Stealer prices - Bel-Metric is your friend. If in doubt, use 10.9. If it has ANYTHING to do with suspension, holding the wheels on, etc. - use 10.9. But use REAL 10.9's...

Every "shortcut" you take will raise the risk - and you'd have to redo them all the right way later. So maybe do it right the first time?

We are not a bunch of Ogres waiting around to pounce (well, most of us aren't) and some of us actually know a thing or two. Do yourself a favor and capitalize on our knowledge, rather than trying to re-invent things. We'll tell you where/how/when you can short cut something, and (more importantly) where you can't. Listen to that and be safe, for your own sake and for those around you.

[ChrisFuture8]

Very well said and heart-to-heart matter of fact IMHO. +8

[m6bigdog]

...this is a project car for me.
...
This is a hobby lol.
...
Who the heck will buy this car ? I was offered $500 by someone saying this was a worthless car.

Cheers !

The most expensive car hobby:
A high-mileage rust-bucket 850 that has engine, electrical, suspension problems, has not been well maintained and the previous repairs have been DYI hacked.
Putting inexpensive Chinese replacement parts from eBay and Rock Auto will only reduce the reliability and value of the 850.
BMW's are not that reliable from new and when repairs are completed with OE parts, so the best you can do is get the dealer parts at a discount.

I've owned and repaired high-end BMW's for 32 years, currently own 2 ('97-850 for 17 yrs), so I know the BMW brand and there is No Budget Too Big when you own a BMW.
BMW = "Big Money Waster"
Keep the 850 and you'll know my experience.
You'll need more than, Good Luck and support from this message board!!

[sshivaram]

Sunil,

Look, while it may seem like some of us are trying to beat you up a little for some of your approaches, there is a bigger picture. You DID use a Grade 8.8 bolt where it calls for a 10.9. That's why people are freaking out, it is unsafe.
Thing is, it may not just be you that gets killed because of some of these mistakes. No, it could be the old lady on the side of the road, your neighbor, or somebody's child.
THAT is why we are telling you NO!

As for Lowes or Home Depot - I would not trust any of their bolts to hold up, no matter what grade they may claim they are... these are mostly complete Chinese crap metal fasteners.

If you want ANY bolt you need, and do not want to pay BMW Stealer prices - Bel-Metric is your friend. If in doubt, use 10.9. If it has ANYTHING to do with suspension, holding the wheels on, etc. - use 10.9. But use REAL 10.9's...

Every "shortcut" you take will raise the risk - and you'd have to redo them all the right way later. So maybe do it right the first time?

We are not a bunch of Ogres waiting around to pounce (well, most of us aren't) and some of us actually know a thing or two. Do yourself a favor and capitalize on our knowledge, rather than trying to re-invent things. We'll tell you where/how/when you can short cut something, and (more importantly) where you can't. Listen to that and be safe, for your own sake and for those around you.

All points mentioned here carry high knowledge, and experience. Everything is welcome. These discussions are good, and very informative.

- - - Updated - - -

The most expensive car hobby:
A high-mileage rust-bucket 850 that has engine, electrical, suspension problems, has not been well maintained and the previous repairs have been DYI hacked.
Putting inexpensive Chinese replacement parts from eBay and Rock Auto will only reduce the reliability and value of the 850.
BMW's are not that reliable from new and when repairs are completed with OE parts, so the best you can do is get the dealer parts at a discount.

I've owned and repaired high-end BMW's for 32 years, currently own 2 ('97-850 for 17 yrs), so I know the BMW brand and there is No Budget Too Big when you own a BMW.
BMW = "Big Money Waster"
Keep the 850 and you'll know my experience.
You'll need more than, Good Luck and support from this message board!!

100% agree. Sadly, everything is made in China today, and its very unreliable, with low quality. The "BMW" branded ignition coils my mechanic used 6 years back were Chinese rip offs, low quality. Each cable had a different resistance, and I replaced it.

As we work through the older models, most parts are NLA, making it harder to get some things repaired.

- - - Updated - - -

The strut bolt i actually used from Lowes:
lowes_bolt.jpg

This is a definite NO-NO ! Will replace it.

This was going to be my next question actually: "why is the BMW spec'd bolt darker in color and the metric bolt i got from Lowe's has stainless steel color, does it imply anything?". Now, its clear they are different grades, and we can't sub it. Unfortunately, the 10.9 grade was mentioned in some random posting i saw on ebay, and its not clear what the bolt grade should be in case we have to find a sub(if the part were NLA).

[sshivaram]

Been reading up a lot about 8.8 vs 10.9.

One can use a 8.8 in place of the 10.9 bolt. An 8.8 can withstand the recommended Torque spec and has nearly the same tensile strength. However, a 10.9 is more brittle compared to 8.8; I am still stumped on how it just snapped with 1 hit/trigger from the Impact wrench.

Usually, using a higher grade bolt in place of lower grade bolt is NOT recommended, since the torque and "clamping" forces are very different on the higher grade bolts.

[LappingLuke]

Bolted joints are a complex subject and even a lot of mechanical engineers struggle with designing bolted joints because there are myriad popular misconceptions and oversimplifications. If you think you know more than the engineer who designed the joint after a few minutes of googling, go right on ahead.

[CD05001CIA]

Oh lord make it stop....

A... HA HA HA ... BAAH HA HA HA. . .... ..... AaaaaH.......

I fear SSV doesn't have the metallurgy background to understand the difference between:

'dross' and a 'jet engine turbine blade'

If he makes a mistake, and he's hauling ass in that eight,,, , he will find out just once. ONE TIME ONLY. (see pic)

P1020350.JPG
Pasadena, CA 2013

Reseda2021.jpg
Reseda, CA 2021

[sshivaram]

Bolted joints are a complex subject and even a lot of mechanical engineers struggle with designing bolted joints because there are myriad popular misconceptions and oversimplifications. If you think you know more than the engineer who designed the joint after a few minutes of googling, go right on ahead.

I am an engineer by profession. I spent over 3 days studying the subject, not just few minutes of "googling". Reviewed many articles, from aviation engineering, and landing gear designs, and realized the importance of using the correct graded bolts. Sticking to OEM is good, and flaw proof. Using a wrong bolt in the wrong place is disaster.

PS: I do know metallurgy, lmao.

[LappingLuke]

Question... if the torque spec on the original 10.9 bolt is low enough that an 8.8 bolt can handle it that's fine, but what advantage was gained by BMW to use the 10.9? Just a way to oversell to dummies who buy luxury cars? Are you SURE that preloading an 8.8 to a stretch that is closer to its failure stress by a % than the 10.9 would be at the same torque will have no affect on the fatigue life? I am not convinced that the 10.9 was chosen for no reason.

[sshivaram]

Question... if the torque spec on the original 10.9 bolt is low enough that an 8.8 bolt can handle it that's fine, but what advantage was gained by BMW to use the 10.9? Just a way to oversell to dummies who buy luxury cars? Are you SURE that preloading an 8.8 to a stretch that is closer to its failure stress by a % than the 10.9 would be at the same torque will have no affect on the fatigue life? I am not convinced that the 10.9 was chosen for no reason.

I am NOT suggesting we go around and change every bolt to lower grade. NOWHERE on realoem.com do we see the grade specification of a bolt.
Both 8.8 and 10.9 can handle the specified torque in this case. A 10.9 grade bolt can handle larger torque and we are not getting into that scenario here.

If you apply more torque to a 8.8, its not as brittle as 10.9, and it won't snap off like how 10.9 died in my hands, but 8.8 will have incurred fatigue and may lose the torque and the threads will shear off. The bolt itself will not break. It all goes towards how much clamping force the bolts can supply, and if the threads in the parts can handle that.

On nearly every bolt that is load bearing on realoem.com, its a 10.9 grade bolt.

Eg: a random bolt from BMW, BMW 31206779384, you type this in ebay. There is just one seller in UK that displays the grade spec on this bolt. You can't find it anywhere else, at least I searched.
bmw_31206779384.png

- - - Updated - - -

In this instance, we have two original bolts, and one new bolt(I will change it lol, and this is all just an academic discussion now), and the new bolt will not be an issue if we continue to use it. However, if we were to replace all 3 with 8.8, I will be highly doubtful. I am sure back in 1989 they have done experiments with this which we can trust and not repeat when parts are mostly NLA.

[sshivaram]

Observe closer... Original upper control arm big end bushings do NOT last 112k miles....

The upper control arms bushings are worn out. When I insert a bolt through the bushing, am able to wiggle it slightly shaking the rubber bushing sideways, but its not terribly bad. With a new bushing, its rock solid.

I tried replacing the bushing, but I can't drive the new bushing straight in ! Keeps going in tilted and screws up. With the tools i have in my garage, and the loaner tools from AutoZone, just can't align it no matter how slowly i try it. I give up.

Few things: I ordered the lowest priced bushing from ebay, about $10, and its the genuine BMW part, brand new, with the "BMW" letters removed with a soldering iron. It was sold as URO Part. BS.
The brand new BMW bushing on FCPEuro costs about $35 a piece, and about $24 for two pieces of Lemforder.

I will order new thrust arms with the pressed in bushings, and hopefully recycle the old ones. The old ball joints are clean, with no play in them. I wish i could just insert new bushings I have in my hand.

240704192_4243216515763672_6082987564803509088_n.jpg
241712355_4258168447601812_4611224032764063412_n.jpg

[sshivaram]

Ordered from rockauto. Closer examination of pictures show original BMW bushings. The one on FCPEuro that has "Meyle" control arms do not show genuine BMW bushings.
Will update here once I get hold of the parts and review/inspect them.
Capture.JPG

[e31gixxxer]

" am an engineer by profession. I spent over 3 days studying the subject,"

I must say how impressed I am, it took me a lot longer, over 4 years as I recall to get the basic qualification.

[Brandon J]

Good luck with the cheaper bushings/arms. We are all dying to know how they work for you. I am no engineer, but I was able to use the C-clamp style press to remove and install thrust bushings straight.

The difference between a good mechanic and a great one is, the great mechanic can still fix things properly when things don't go well. Rust, corrosion, things not being straight, poor access, there isn't a proper tool, etc., the great mechanic can get out of a situation. I was able to improvise to ensure things were straight using the C-clamp style balljoint/bearing press. I've done maybe 5 dozen bushings on various vehicles using the C-clamp style before purchasing a proper shop press. Some bushings, like on solid axles or in-subframe suspension bushings, have to still be done using the C-clamp style press or using a homemade tool.

[rjjablo]

I failed out of engineering school. Replaced mine with Moosehead and a C Clamp style along with an Impact. Going to get a proper benchtop press for the rear end this winter. 22 bushings will justify the expense.

[Brandon J]

I failed out of engineering school. Replaced mine with Moosehead and a C Clamp style along with an Impact. Going to get a proper benchtop press for the rear end this winter. 22 bushings will justify the expense.

I'm not an engineer, but go for the 20-ton press as it's a good idea to have the extra capacity. I broke my two yr old 12-ton press while doing the rear of the e31 bearing/bushings and then resorted back to the C-clamp style for the remaining I had. I have already pressed bushings and wheel bearings on six other vehicles with the 12-ton shop press so it paid for itself several times over.

[petejk]

I also opted for a 20 ton over a 12 ton press.
The price difference (Harbor Freight) wasn’t that great.

I was able to use the press for rear suspension rebuild, disassembly and reassembly of my diff, and pressing in a pair of front control arm moose head bearings.

Definitely paid for itself!


Sent from my iPhone using Tapatalk

[sshivaram]

Good luck with the cheaper bushings/arms. We are all dying to know how they work for you. I am no engineer, but I was able to use the C-clamp style press to remove and install thrust bushings straight.

The difference between a good mechanic and a great one is, the great mechanic can still fix things properly when things don't go well. Rust, corrosion, things not being straight, poor access, there isn't a proper tool, etc., the great mechanic can get out of a situation. I was able to improvise to ensure things were straight using the C-clamp style balljoint/bearing press. I've done maybe 5 dozen bushings on various vehicles using the C-clamp style before purchasing a proper shop press. Some bushings, like on solid axles or in-subframe suspension bushings, have to still be done using the C-clamp style press or using a homemade tool.

Update: I was able to insert the bushing accurately, using the C clamp rental tool from Autozone. Go slowly, keep aligning, and DON"T use impact wrench to push it in, since alignment will screw up in a second.

Now, I have 3 control arms. (Videos follow the numbered arms)

1. Original one, the ball joint is super loose. Has 123K miles, from 1995. I have pushed in a new bushing, appears to be Genuine BMW. The ball joint rubber boot is not torn, there is no vertical movement of the ball joint, but its so loose, i can twist it around using my thumb. (On the M5 board, someone did say as long as the ball joint rubber is not torn, it can be re-used, and is designed to live for the life of the car).

2. The LEFT arm from RockAuto was $25. The ball joint can be moved with the thumb, its not loose. However, its very clunky, squeaky, and extremely rough in its movement. I can feel the ball grinding against metal parts, just not a good piece I guess. I have marked this for return and asked for replacement already.

3. The RIGHT arm from RockAuto was again around $25. The ball joint is super stiff, doesn't move with thumb. However, using a socket, i could leverage and move it around. The movement is extremely smooth, looks air tight, fire proof, bullet proof ! It came in a plastic bag labeled "Made In China". The arm itself looks awesome and clean, with a brand new bushing that has NO markings on it. Its also not Greenish in color, rather a bit bleached green. I am keeping this.

Videos:
1. https://www.facebook.com/10000226096...6920189019435/

2. https://www.facebook.com/10000226096...8197202531668/

3. https://www.facebook.com/10000226096...4343518591137/

THANKS!! Appreciate all feedback.

[petejk]

Is the never ending control arm bushing saga going to end at some point?


Sent from my iPhone using Tapatalk

[sshivaram]

Is the never ending control arm bushing saga going to end at some point?


Sent from my iPhone using Tapatalk

Hope to wrap up front end on this 850ci by next week ��
I am working on front end suspensions on 3 of my cars simultaneously...all with 100K+ miles.

[Brandon J]

Since you are an engineer, let us know how your decision goes and when you finally get it installed with some miles driven.

ROFL, I work on more than 3 cars with over 100k miles. In fact, 2 have more than 160k miles, had one that was 40+ yrs old, etc. It doesn't take me weeks just to do complete front suspension. That's what a Saturday is for with any spillover onto Sunday. Maybe I'm efficient because I don't cheap out on parts. Compared to the engine work which is more detailed, the front suspension is pretty straightforward.

As an engineer, it is kind of funny to hear your reasoning and justifications on parts.

[sshivaram]

Since you are an engineer, let us know how your decision goes and when you finally get it installed with some miles driven.

ROFL, I work on more than 3 cars with over 100k miles. In fact, 2 have more than 160k miles, had one that was 40+ yrs old, etc. It doesn't take me weeks just to do complete front suspension. That's what a Saturday is for with any spillover onto Sunday. Maybe I'm efficient because I don't cheap out on parts. Compared to the engine work which is more detailed, the front suspension is pretty straightforward.

As an engineer, it is kind of funny to hear your reasoning and justifications on parts.

Its a slow hobby, evaluate everything, and work when time permits. My weekends are never free. I get to spend about 1 hr a week on my car.
I was gonna wrap up everything yesterday, but the part i got is cranky; yes its cheap - you get what you pay for. I am sure if i spent $800 ordering Genuine BMW parts, the work would be over in 1 hr.
My budget on these old expensive cars is very limited sadly. Those are my limits. I want to see if the lowest priced solution works.
I said I am replacing front suspension on 4 of my cars now, so I can't blindly throw away $1500 on each. I have to be more efficient on getting it done. Not in any rush lol.

[Brandon J]

Everyone has their time constraints and budgets. Your time management is your own issue. Also having old cars is your decision, especially if you can't afford to properly fix them with the right parts.

Regarding the bushings and control arms, save everyone else time on this board and just get it done your way. You are an engineer who chose cheap parts and have your own justifications. Our decades of experience here just wants you to install them so you can get your own first hand experience.

[sshivaram]

Everyone has their time constraints and budgets. Your time management is your own issue. Also having old cars is your decision, especially if you can't afford to properly fix them with the right parts.

Regarding the bushings and control arms, save everyone else time on this board and just get it done your way. You are an engineer who chose cheap parts and have your own justifications. Our decades of experience here just wants you to install them so you can get your own first hand experience.

Watch this video pls, tell me if this ball joint is good to go back on the car (I have another gentleman on a different board, with same decades of experience, saying its good, because although its looks loose with miles and age, the structure isn't ruptured, so can be saved !!)
1. https://www.facebook.com/10000226096...6920189019435/

We are short of Genuine Original items on the e31; many parts are NA. We have to refurbish; 3D print printable parts; and in many cases live with flaws going forward.

I am going to put the old arm back, with a new BMW bushing and see how it drives. But technically, to me, the new arm i have from China looks awesome, has the same "weight" as old one, which tells me a lot in terms of its composition in simple terms.