So I read other threads and posted another about this oscillation I get under acceleration if there is any slack in the drivetrain. I can't figure out If it is the backlash on the diff, maybe axles, or possibly (if its dual mass) the bushings that hold the two masses of the flywheel together??


There is a looseness somewhere in the drivetrain, the flex discs and center bearing are fine. Could backlash get this bad? Car does have ~400k.
If you lift off the throttle you get an oscillation, but if you try to get back into it without either easing into it or flooring it (so part throttle) this thing will start shaking back and forth harder and harder until it rips itself apart.
I have trained myself to drive around this issue, but would love to know what is causing it.


Also: the tabs on the rear seat, which direction to I push/pull them to remove it? towards the rear, or towards the front of the car?

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190D SOLD
2.5 non turbo
5 speed manual transmission
Build date: December 1985
W211 E320 CDI
W126 350SDL
X204 GLK 250 Sans Bluetec