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Car pulls to the right

2000 BMW 528i with Sports Package. Recently had all tires and shocks and struts replaced, followed by alignment. When I got the car back, it was pulling to the right (used to be very straight before the change). Mechanics thought first that it was tire pull. Several tire switches, including a set from a different manufacturer - no change, not tire pull. I asked them to check the parts used and they found they had the wrong struts and shocks for the suspension type (using Boge Sachs after market parts). I thought that was it, but after putting the right ones on, still the same problem. A series of 8 alignment checks from an alignment specialist revealed that the left side is riding about 3mm higher than the right (well within the 10mm limit) - no other flaws. They are BMW specialists and have been my mechanics from 50k to the current 130k - no problems. I am stumped and they seem to be flummoxed as well. All the recommended procedures have been followed - by the book - in installing the struts/shocks (car on its weight before tightening, etc) and aligning (weighting the car, etc), so I am really looking to see if someone has run into this problem and had it resolved. The car was on the wrong shocks and struts for 100 miles or so while other tests were being conducted. Feedback from other sites is that this should not have left permanent damage to explain the pull that remains.

The 10 MM spec may be within the limits but it would concern me that a spec would have that much leeway in it. The 3 MM is not much of a concern; just saying…

Since this is apparently not a case of tire bias, do you have a printout of the specs on the alignment?
What does it state about caster and camber specifically?

Don’t have the latest, they have really gotten it much tighter, but the original when I got it back were camber -0.2, caster -0.3; left -0.6 and 5.9, right at -0.4 and 6.3. (I know very little about cars).

Have you moved the left tires to the right and visa versa? The entire wheels I mean, tires and rims, exchanged them left to right? Should onlyu take 30 minutes or so to test … If not, that’s the first thing I’d do. I’m assuming you’ve already done that and it still pulls to the right. … hmmmm … how about this: Part the car on a level surface and measure the height of each side yourself. Do you confirm the 3 mm difference? It seems to me a car should have less than this left to right, but it’s hard to imagine 3 mm would make for a really noticeable pull to the right. Next try this: Try to find a road or even a large parking lot that is as flat as possible left to right, it has only a small amount of crown in other words. Does it still pull as much? If it doesn’t pull when the road is flat left to right, it is likely there remains some problem with the new suspension parts or tires they installed. The suspension and tires, if they are working properly, are supposed to prevent pulling even if the road it tilted to the right, which most roads are.

The tire switches, including rims, was done. Not the source. The pull is present even on a very flat road. The 3mm was measured by the shop on a level surface. I am thinking that this may be due to some collateral damage during installation - probably very hard to isolate. I wonder if the installation of the worng part initially could have pulled/stressed something around it in the suspension. They are taking the car to an alignment specialist (shop that only does alignments). Hoping for some results there.

The crown of a road, as common in a 2 lane highway is high in the center and slopes downhill from there to aid in water drainage. This can cause a car to pull to the right. The test would be to find a road or lane that slopes to the left and see if you still have the same issue. Some cars are more sensitive than others.

The alignment specialty shop is the way to go. Until the proprietor retired, I used a great alignment shop. Dealers and tire shops made appointments with him even though these shops had alignment racks. When the dealer or tire shop wass stumped and the customer complained enough, the dealer or tire shop sent the vehicle to this man. He could always get to the bottom of the problem.

An alignment specialty shop seems the right next step. They do this kind of job every day. I can’t imagine they can’t figure out what is causing your steering to pull to the right. Best of luck. Let us know what you find out.

I don’t understand the measurements posted but it does not matter for my reply. Front wheel caster should normally be identical for each wheel or steering pull will result. Otherwise, if caster adjustment is possible, you can cancel pull to the right by adding a very small amount of caster to the right front wheel or decreasing caster on the left front wheel. I wonder if your “A” frame positions are exactly as they were before your front end work was done. If there is no caster adjustment provided, then an adjustable caster plate will do that if you can find one to fit. I have another way, elongate the strut mounting holes at the top of the shock tower but you would not want me to use that crude method on your BMW. There are other possible solutions and I have no knowledge of any of your alignment settings including those of the rear wheels and the position of the rear wheels relative to the front wheels (thrust alignment). A long distance reply may only permit a guess.

You need an alignment person with a little more knowledge than simply being able to operate the alignment tools.

I can’t understand your caster and camber descriptions as you stated them, and that information would be very helpful in determining if your pull can be eliminated by changing something. I also suggest taking the car to an alignment specialist. Many people seem to think that as soon as all the numbers are green on the display that you are good to go and there will be no problems. This is not always the case.

Thank you all for your comments. The good news is that the mechanics have decided to do exactly what most of you have suggested - take it to an alignment speciality shop. It may take till Mon to get the car looked at, but I am really hoping for a solution - more optimistically after seeing your comments.

For the caster and camber numbers, I know very little about cars - just copied what came with my repair bill. The “before” numbers were outisde the limits; the “after” numbers, which I sent out to you, are within the limits. They have got them even closer to “zero” since then - without any effect on the pull problem.

Sounds like someone removed a factory shim and did not replace it. My brother inlaw had the same issue on a lexus. On the factory floor they fix body issues with a shim. It is not in the repair book because it is not supposed to be there. It took 4 months for the lexus folk to agree that it needed the factory shim.

euryale1,

This is exactly the kind of info I was hoping to find from posing this question. I will pass it on to the mechanics. My assessment, which I passed on to them was that this repair could have gone awry from one of four sources - poor alignment, wrong parts, wrong installation or collateral damage. This one falls somewhere between the last two categories.

Thank you.

The specs provided were not laid out real well so it’s hard for me to decipher them. What I was looking for was the possibility of the caster being way off.

The ride height discrepancy can also be caused by a bent suspension component. (control arm, coil spring, damaged strut tower, or even a bent steering knuckle)
One apparently minor collision, pothole, or curb strike could do it and it would not be visible to the naked eye.

Be sure they check for a dragging brake, too. Every possibility should be looked at.

ok4450 - All the specs were within the limits. If there are damaged parts as you have suggested, I hope the check from the alignment shop expert will find it. Should know in a couple of days.

the same mountainbike - They did check for any brake related drag, but could not find any.

euryale1 - How did your brother-in-law’s mechanic figure out where the shim was supposed to be? Did they have to contact Lexus and dig it out of some records? I’d like to know, in case this needs to be chased down.

Go back to that repair bill. There should be a left caster, left camber, right caster, right camber, left toe, right toe and total toe. The numbers you gave did not follow that format. You should have a printout from the computer on the alignment machine, two actually, one before and one after.

Since this car has a fully independent suspension and you had the shocks (rear) changed, did anyone check the rear wheel alignment? Have you had anyone follow you to see if your car is “dog trotting” (aka “crabbing”) down the road?

keith,
They have done several checks on the alignment numbers and have realigned to get as close to the nominals as possible in an attempt to solve this. They have done alignment on this car twice before with excellent results. I don’t think this will be a case of being over the limits on the caster, camber and toe settings. They did check rear alignment as well. The car behaves pretty much perfectly, except when you let the steering wheel go, it pulls to the right after a few seconds. If you leave it, it keeps pulling that way. The mechanic reports that the pull gets slightly stronger the longer you leave it.

The problem has finally been solved. It turned out to be the caliper on the right side intermittently engaing the brakes. The amount of engagement was so slight that the usual method to detect this - checking the temperature on brake components after driving a bit - did not show appreciable difference (about 6 deg). There was also no appreciable wear on brake parts that would have indicated this problem. After running out of all avenues, the mechanic probed this temperature difference further by spinning the wheels by hand. The right one went 1.8 revs compare to over 3 on the left. That gave him the clue. He confirmed it by having his colleagues repeat the test. Solved by switching th calipers on the two sides. Car stays straight as an arrow, as it used to.

Thank you all, once again, for your helpful suggestions.