E28: Bad Diff/ Bad Driveshaft?

[JNasti]

Wondering if any of you guys have had this problem?
1987 535is 5 speed with 220k. When giving it gas at all doesn't matter if I'm up in rpm or low and or when letting off gas. It almost clunks and then thrusts forward while gassing or backwards when letting off the gas. It almost bucks at low rpm. I try to drive it slowly while accelerating to remove this "bucking" because you can see the car doing so from a ways away. Some threads I have read state U-Joints or carrier bearing maybe the driveshaft itself. I have also read possibly a differential problem or diff mount/bushing. Wondering if anyone else has had this problem.

Thanks guys

[M-System]

There are other possibilities, but my guess is diff mount, or rear subframe bushings.

[South26]

If bad diff mount you would notice it going backwards with causing a clunking. If it was your subframe bushings it would feel like you are being kicked in the rear when you start up from a stand still. Sounds like drive shaft or maybe tranny mounts. I would look at cab and the mounts.

Andy

[be34st]

I had a clunking problem with my E34 when accelaerating. I changed my Center Support Bearing and that fixed the problem. I didnt have any bucking though.

[JNasti]

If bad diff mount you would notice it going backwards with causing a clunking. If it was your subframe bushings it would feel like you are being kicked in the rear when you start up from a stand still. Sounds like drive shaft or maybe tranny mounts. I would look at cab and the mounts.

Andy

Great thanks, my dad has a lift at his work but we work opposite shifts. Trying to get on that lift soon and check out underneath. I'm looking into changing the diff mounts just because. Hopefully I can find the problem.

[FLG]

If the mounts/bushings are as old as the car (chances are high) your gonna need new mounts all around. Diff, subframe, and trialing arms. Most likely motor mounts, transmission mounts, and front control arm bushings as well. Possibly driveshaft flex disk and center support bearing too.

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[EREKSHUN]

Guibo

[LavaSurfer]

My 528e also does this to some extent. Ive replaced the driveshaft as two u-joint were going out, CV axles and all rear subframe bushings and diff mounts along with motor mounts. All this took most of it away but its still there. The only thing left is the dual mass flywheel....and I'm not messing with that until it gets worse.

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