My 300SD pulls to the right...

[tagma_ike]

I picked up my first Mercedes (300SD) project last December and have loved working on it over the last year. Replaced and refreshed many items along the way. Now I am at a loss at this point. Here is the history of things that have transpired with my latest undertaking – the rear end rebuild.

The original rear lower trailing arms were rusted very badly and the right one actually broke at the hub. I made a visit to my local MB bone yard and returned with two un-rusted arms. After removing the right arm and installing the newer arm I sadly discovered that I could not bolt the brake caliper to the hub without it pushing off the rotor?? It turned out that both of the un-rusted arms were bent at the caliper bolt location (some son of a #@$@#%) had bent them most likely during the insertion of a fork lift as the donor car was not wreaked. So another trip back to the yard produced another set of arms which now needed bearings. After reading through the threads on rear bearing I took the arms to my local indi and had them do the job. Great, now it was time to put the car back together, with all new rubber in the rear including sub frame mounts, diff mount and flex discs. Replace all rear disc brake components as well.

The car now drives like a dream in the rear, no more bounce or sway and even breaks going straight ahead instead of trying to seek out the nearest ditch when you brake hard. I am very happy with the results, except for it now wants to wander over to the right when you are running over 45mph. It's not much, but very annoying. So I tried new tires (hated the ones that were on the car in the first place). The results were the same, except no more square tires... So back to the tire shop for a front-end alignment. This resulted in no noticeable difference in the way the car pulls to the right. I have tried putting on the parking brake while running down the road to see if that would make any difference, it did not.

I did notice that after the indi replaced the rear bearings that one of the hubs was much easier to rotate than the other (loose bearings?), I just don't remember which hub it was (duh!). Could this be the source of my problem? There are no adjustments in the rear that I can see.

So I am seeking the forum expert’s advice of things to try next?

I plan on returning to my local indi (Erol's Autobahn in Nashville) and seeing if he has any ideas as well.

Thanks

[tagma_ike]

Originally Posted by ellington

i'm assuming that your 300sd is of the W116 vintage. check all of your rubbber bushings on the front control arms, (upper and lower.) also check for play in all tie rod ends and ball joints. if everything up front looks good, do a thrust line alignment, not just a front end alignment. a thrust line alignment takes into account the actual placement of your rear suspension and aligns the front accordingly. if the rear suspension is out of synch with the front, you could get drifting pulling issues.

Thanks Ellington, I should have mentioned the year and model type in my post... It's a 1984 W126 chassis. Good point on the thrust line alignment, I will have to look into that. The front end appears to be tight and I had no problems before the rear end rebuild.

[david s poole]

get the rear wheel alignment set up.