I have a 1979 323i, nicely painted with a fresh m20 conversion- however the suspension is terrible.

I've changed subframe mounts recently.

The best way to describe the noises is if you let off the gas the car will rock back and forth. When going around a corner there is a clunking in the back. There also appears to be a bit of grinding when taking off slowly.

I'm pretty sure the front control arm bushings are shot, but what's going on in the rear? Could all this be from trailing arm bushings?

THANKS

This really does sound like sub frame bushings. I would inspect them if possible. Or check out the FAQ for the DIY urethane mounts. I actually did this for the second time last night. My 323i had the clunk on turns. Same with my 320i and when I replaced the mounts the rear tightened up a good amount and the sound went away.

Subframe bushings were just done. Is it possible they were bad? They could have been new old stock and I had them sitting around for 2 years before I installed them.

Could they have been installed wrong? seemed like there was really only one way for them to go in.

Subframe bushings were just done. Is it possible they were bad? They could have been new old stock and I had them sitting around for 2 years before I installed them.

Could they have been installed wrong? seemed like there was really only one way for them to go in.

You never know with this old rubber. Its possible the sleeve just gave out.

What about the diff carrier bushing?

You never know with this old rubber. Its possible the sleeve just gave out.

What about the diff carrier bushing?

That's a good suggestion. I'll check it tonight. Is it available from most parts places or do i have to go to BMW. anyone have a part #?

You would be really suprised...I had a problem where it felt like the rear lurched terribly to the left when i would turn right. I replaced the subframe bushings in the back with homemade urethane ones and the trailing arm bushings looked to be solid enough (but still need to be replaced...) long story short, the rearend refresh didnt solve it, my car was handling terribly because the drivers side front lower control arm bushing was shot and the bolt was loose...causing an incredible camber change when turning right.

Do you feel like you have to countersteer slightly when the car rocks or lurches even though you know you are not drifting? Thats what I had to do. Keep us posted on what you find!

Do you feel like you have to countersteer slightly when the car rocks or lurches even though you know you are not drifting? Thats what I had to do. Keep us posted on what you find!

I find that if i'm in second gear accelerating in a straight line and take my foot of the gas the car will rock back and forth. I think there may be multiple issues going on here.

rocking, especially when backing off the throttle can be caused by play in the diff too.