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BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Suspension | Brakes | Chassis > Negative camber



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      01-08-2016, 08:28 AM   #45
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Originally Posted by feuer View Post
Correct, that is why there are many thread about cars with uneven height especially in the rear. Usually left to right is never identical not even from factory. It will ride 100% OK but if you look closely or better yet measure or scan you can tell that there are different. On older car might be even more drastic. Bushing will wore out at different rate. Same with springs and shocks. So the car will be aligned perfectly but how the body will sit on the frame it will not. Also accidents....
Thanks, very helpful! I did measure from fender to bottom of rims on all corners and it was surprisingly close, expected greater differences but then the car had been corner balanced so maybe that had something to do with it.
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      01-08-2016, 08:29 AM   #46
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Originally Posted by W37V View Post
Surface was level.
Both tires are inflated to 38.5
Both tires are brand new. They have about 1000 miles on them.

iPhone cable or any string (to be used as a pendulum) is sufficient to show the difference in distance from it and the measuring point. Pendulum will be at 90 degree angle, so any deviation from it can show the angle.
That is all fine but not how alignment is measured. is done how the wheels are relative to the ground not the cars body.
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      01-08-2016, 08:33 AM   #47
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Originally Posted by justpete View Post
Thanks, very helpful! I did measure from fender to bottom of rims on all corners and it was surprisingly close, expected greater differences but then the car had been corner balanced so maybe that had something to do with it.
Yes, and that is to be expected because you have coilovers which allow adjustments and also pretty much the rest of the suspension, like bushings and such has been replaced with aftermarket parts that would yield significantly much less give. On stock fully OEM car is nothing like that.
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      01-08-2016, 08:34 AM   #48
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Originally Posted by feuer View Post
Even with alignment spot on the wheels will "appear" different since the car is not 100% symmetrical. Was the surface completely flat? Were the tire inflated properly? Were the tires evenly wore? Probably one side is higher than the other! A lot of variables! and most definitely you can't measure with iphone cable and pad lock. Also, lifting the car from under the spring arms (#4) will hurt nothing.
I know the force the wheels see while driving is transmitted to the suspension arms and theoretically applying a lifting force to the arms should be ok because of this but the force from the wheels is transmitted through joints having compliant coupling making the point of application different from that applied by a jack, or at least possibly different. The application point is visible in the picture, I think, and looks like it was distributed on the trailing link and the bushing location on the wheel carrier and possibly on some of the spring arm, hard to tell, maybe the mark on the trailing link is after lifting brought the jack into contact with the link. Could this potentially cause some damage to the bushing/joint if not the trailing link? Doesn't look like it but I'm trying to follow the stresses to see how similar they are to those applied by, say, a chuckhole or something. The trailing link should be ok for a normal lifting force but not for a transverse force, right? Thanks for the help.
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      01-08-2016, 08:36 AM   #49
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Quote:
Originally Posted by feuer View Post
Yes, and that is to be expected because you have coilovers which allow adjustments and also pretty much the rest of the suspension, like bushings and such has been replaced with aftermarket parts that would yield significantly much less give. On stock fully OEM car is nothing like that.
Oh yeah, that'd do it, thanks. The compliant bushings would tend to not settle equally unless forced to do so by rocking the car, rolling it forward and back, etc., duh.
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      01-08-2016, 08:46 AM   #50
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Quote:
Originally Posted by justpete View Post
I know the force the wheels see while driving is transmitted to the suspension arms and theoretically applying a lifting force to the arms should be ok because of this but the force from the wheels is transmitted through joints having compliant coupling making the point of application different from that applied by a jack, or at least possibly different. The application point is visible in the picture, I think, and looks like it was distributed on the trailing link and the bushing location on the wheel carrier and possibly on some of the spring arm, hard to tell, maybe the mark on the trailing link is after lifting brought the jack into contact with the link. Could this potentially cause some damage to the bushing/joint if not the trailing link? Doesn't look like it but I'm trying to follow the stresses to see how similar they are to those applied by, say, a chuckhole or something. The trailing link should be ok for a normal lifting force but not for a transverse force, right? Thanks for the help.
Is VERY unlikely for the spring arms to get damaged if used to lift the car, or anything they are directly attached to.
That is the reason why e36 and e46 are ripping the rear subframe floor when sitting on lowering and stiff springs in particular. The arms were able to tolerate the extra stress but the body was not. If the arms are weak they would have buckled under stress with stiff springs.

The trailing arm will not to be used for lifting, towing or anything of that manner. Is designed to buckle in the middle to prevent damage to fuel tank. That is why I have advised people not to upgrade those. Very little benefit for very big potential risk. That is why the trailing arm is the only piece shared with the M3. Is designed to fail first from all rear suspension components.
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      01-08-2016, 08:51 AM   #51
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Quote:
Originally Posted by justpete View Post
The trailing link should be ok for a normal lifting force but not for a transverse force, right? Thanks for the help.
This is what I have learned from just working on these cars:
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      01-08-2016, 08:52 AM   #52
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Quote:
Originally Posted by feuer View Post
Is VERY unlikely for the spring arms to get damaged if used to lift the car, or anything they are directly attached to.
That is the reason why e36 and e46 are ripping the rear subframe floor when sitting on lowering and stiff springs in particular. The arms were able to tolerate the extra stress but the body was not. If the arms are weak they would have buckled under stress with stiff springs.

The trailing arm will not to be used for lifting, towing or anything of that manner. Is designed to buckle in the middle to prevent damage to fuel tank. That is why I have advised people not to upgrade those. Very little benefit for very big potential risk. That is why the trailing arm is the only piece shared with the M3. Is designed to fail first from all rear suspension components.
Thanks, I remember reading about that now, makes perfect sense.

Originally, the description of the lifting points was given as the trailing arms/links and there's some marking on it that looks like a lift point on a jack which seemed disconcerting. They don't seem bent and its cross section is such that bending one might be difficult but ya never know how careless someone might've been with a jack. Hopefully maybe it'll come down to something totally non-critical.
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      01-08-2016, 08:54 AM   #53
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Quote:
Originally Posted by feuer View Post
This is what I have learned from just working on these cars:
That makes sense as it's designed to fail in that manner from a transverse force but now I'm thinking it would take even greater force to bend it so it buckled upward instead, right?
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      01-08-2016, 08:55 AM   #54
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Quote:
Originally Posted by feuer View Post
This is what I have learned from just working on these cars:
And that's an M3 spring arm, right? Definitely not the stamped metal non-M arm...
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      01-08-2016, 09:04 AM   #55
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Quote:
Originally Posted by justpete View Post
And that's an M3 spring arm, right? Definitely not the stamped metal non-M arm...
Correct, and only benefit is allowing better shock articulation so the suspension will be more compliant under load. Don't think is stronger though. F30 are same design as e90x M3 just stamped.
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      01-08-2016, 09:10 AM   #56
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Originally Posted by feuer View Post
Correct, and only benefit is allowing better shock articulation so the suspension will be more compliant under load. Don't think is stronger though. F30 are same design as e90x M3 just stamped.
Yes, knew about the difference in shock mounting, changed to clevis on mine iirc as it came with the new shocks. But I'd swear the stamped structure can't be as rigid under twisting stresses as the cast part, could easily be wrong though, usually am.
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      01-08-2016, 09:16 AM   #57
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Quote:
Originally Posted by justpete View Post
Yes, knew about the difference in shock mounting, changed to clevis on mine iirc as it came with the new shocks. But I'd swear the stamped structure can't be as rigid under twisting stresses as the cast part, could easily be wrong though, usually am.
For twisting stress, yes, I was thinking more along the lines on bent vs broken off in case of an impact during accident.
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      01-08-2016, 09:19 AM   #58
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Originally Posted by feuer View Post
For twisting stress, yes, I was thinking more along the lines on bent vs broken off in case of an impact during accident.
Understood, thanks. Was thinking the stamped swing arm could be twisted by improper application of lifting forces if some of it went to the trailing link instead of the majority of it on the knuckle. Seems farfetched now though...
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      01-08-2016, 09:39 AM   #59
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Quote:
Originally Posted by Camman View Post
Go to the dealer or an alignment shop and see what they measure.

From the pictures it's hard to tell how much camber is there. It looks like you have the super sunk 16in wheels. From the pictures it doesnt look that bad but I'm no expert and they definitely shouldn't have been lifting the car where they were doing it. Again, an alignment shop will measure all the specs the car is currently running.

Also, how many miles are on the car and have you had any suspension components replaced since owning the car?

Keep an eye on the tire wear, if something is really messed up that is throwing the toe out of spec, it will chew through the tires. I had a friend drive from Dallas to Houston with a bad toe alignment and the inner tire was bald by the time he got to Houston lol
Car is 2011 with 57k miles. Stock suspension. Nothing was ever replaced. It's on 18 inch wheels. And was never in an accident.

I checked tire wear and didn't see anything obvious as tires have about 1000 miles on them (drive from Florida to DC )

I get an alignment done once a year because DC roads only meet a theoretical definition of a paved road and are some of the worst. Alignment was always done at the dealership. Last alignment was done in May 2015.
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      01-08-2016, 10:24 AM   #60
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Originally Posted by W37V View Post
Car is 2011 with 57k miles. Stock suspension. Nothing was ever replaced. It's on 18 inch wheels. And was never in an accident.

I checked tire wear and didn't see anything obvious as tires have about 1000 miles on them (drive from Florida to DC )

I get an alignment done once a year because DC roads only meet a theoretical definition of a paved road and are some of the worst. Alignment was always done at the dealership. Last alignment was done in May 2015.
at 57k on roads as bad as you say they are the rear shock are either dead or on their last leg making any good alignment short lived since all the impact related stress would be directly transmitted through the rest of the suspension components.
Next time you do alignment asked to mark the eccentric bolts with paint marker so you can monitor alignment settings if any.
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      01-09-2016, 11:08 AM   #61
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Quote:
Originally Posted by feuer View Post
This is what I have learned from just working on these cars:
Lol, dont think e9x M3 was made in 2003.
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      01-09-2016, 12:16 PM   #62
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so, maybe i was just freaking out for nothing.

here is the alignment sheet.
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      01-09-2016, 12:23 PM   #63
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Originally Posted by W37V View Post
so, maybe i was just freaking out for nothing.

here is the alignment sheet.
w00t! Really glad I was wrong. Were they able to explain the feeling of the trunk being full of water?
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      01-09-2016, 01:13 PM   #64
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Quote:
Originally Posted by justpete View Post
w00t! Really glad I was wrong. Were they able to explain the feeling of the trunk being full of water?
he said that it was due to a softer tire wall on DWS 06 causing a lot of tire roll. he said that after driving on DWS 06, my sensitivity to notice the roll might be heightened.

my fiancé drove the car and said that on AS/3s the car feels the same like before tire change, so there might be something to his theory.
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      01-09-2016, 01:26 PM   #65
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Originally Posted by W37V View Post
he said that it was due to a softer tire wall on DWS 06 causing a lot of tire roll. he said that after driving on DWS 06, my sensitivity to notice the roll might be heightened.

my fiancé drove the car and said that on AS/3s the car feels the same like before tire change, so there might be something to his theory.
Wouldn't have expected it to be that great a difference, learn something new every day, thanks.
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      01-09-2016, 04:31 PM   #66
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Quote:
Originally Posted by Cloud9blue View Post
Lol, dont think e9x M3 was made in 2003.
LOL, yes, just the camera date is off!
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