coobah

Hi.

When I bought the car it had a snapped rear subframe bolt (left rear one). My rear wheels weren't straight camber wise. Left one was like 0 camber and right one was in more negative than it should. Also the car was pulling to one side a bit. (Actually I can't imagine people riding with snapped subframe bolt without feeling it)

I dealt with the problem but when I did it I had the car jacked up by only one side. I also needed to loosen the other bolt on that side so I could lower the subframe enough to get with a TIG torch over there (I also changed the other bolt preventively).

The camber seems good on both sides now but... my car still pulls just a bit and it pulls to the other side than it did before.

I don't know how the car was handling before but all the suspension parts are still from factory, they're still in a really good shape and it surely wasn't in any accident so... I have a feeling that I did tighten the rear subframe not straight/not as it was before. Is this possible?


Are there any ways to make sure that rear subframe is mounted perfectly straight?
- Maybe I should jack the car up evenly, loosen the bolts, lower the car perfectly level and then tighten them? (Seems hard, especially having no car lift)
- Maybe I could jack the car up. Loosen all bolts and tighten them all down evelny - let's say half a turn, one by one each time?? (seems a lot easier with car jacks).
(Getting them torqued to spec is a different story and I'm familiar with it)

I'm going to do a full suspension geometry check/adjustment in a shop soon but I'd like to get my subframe straight first if there would be such an option.


BTW: Is it wise to replace the other side bolts preventively getting there anyway? (I have two more in my garage drawer)

Pmarino

Id check all the bushings, otherwise not sure. Could it be bent? https://mbworld.org/forums/w211-amg/...placement.html
The rears are set - from the factory. You can get toe and Camber arms that are adjustable.

coobah

I meant more like... I wonder if it was possible (because of my way of raising just one side of car, unbolting just one side of the subframe), to bolt the subframe back not straight "within the limits of the other side bushings flexibility" which could affect any of the rear suspension geometry??? (the camber is ok ATM)

Pmarino

Yes.... I'd be lifting from the diff. Hopefully a tech will chime in for you.

coobah

Lifting from a diff seems a very good (quick) idea. I just wonder if any difference of pressure in the air bags can alter the job? Should I deflate the rear suspension via STAR for it? What is "the proper" way to mount the subframe?

E63007

Yes, you definitely must deflate the air from the rear Suspension when attempting to mount/dismount your rear Subframe. The WIS Calls for both Front and/or Rear Subframe Bushings to be replaced in pairs, as this ensures the Suspension to remain in alignment. So that means to jack up the rear and use stands, then use jack or Tranny lift to apply pressure to the diff, then remove either F or Rear Subframe bolts (Not all!!) then lower jack/Tranny lift enough to remove/replace Bushings then, then raise Diff and insert bolts and tighten to spec and then do other side similarly. This requires for you to have StAR/DAS/Xentry and I must say it would be a good investment if you ever want to do any work on your car involving the suspension (i.e.-ride height), engine, electronics. I guess theoretically you can deflate the rear manually, but to inflate it requires STAR so why bother without it?