Really need some help with this guys...........
Car: 245 SE auto trans. 236Kmiles IPD bars, Boge Turbo gas shocks.

Symptom: Rumbling and vibration on deceleration.

Details: Rumbling and vibration is felt throughout the car including the steering wheel , hard to pinpoint source, front or rear. Rumbling and Vibration (hereafter as R&V) occurs when the car is slowing, brakes NOT applied, trans in NEUtral. Braking does make the R&V worse, but it is still very apparent when coasting down.
Accelerating or steady state in forward- no R&V.
When accelerating in reverse, R&V is apparent.
Coasting in reverse - no R&V.


Problem is slowly getting worse. 6 months ago I noticed a slight rumble on deceleration at 50+mph, as if the exhaust was shifting onto the body somewhere.
Then was noticeable upon braking, finally occuring whenever lifting off the gas (coasting).

I have eliminated the brakes and engine mounts as problems because it occurs in neutral and when not braking.
INspected under car. no play in driveshaft universals, center mount moves a bit but is not loose. Discovered axle/trailing arm bushing bad on right rear, just replaced it (see horror show story soon), seems to have made the problem WORSE!

Analysis: Whenever the weight shifts forward as when decelrating the V&R occurs.
Seems it may be related to the torque reversal produced by the rear wheels when slowing, which I think narrows the suspected parts to the rear suspension, driveshaft, maybe the transmission. Transmission seems fine, no clunk when engaging or on/off gas. Only transmission problem was my daughter reported the car seemed to be staying in gear too long as she accelerated, presently the OD does not work, solenoid or wiring, I suspect.

Of course, what makes this worse is it's my daughter's car which she drives to work everyday, She's been a good sport about it, not hasselling me, but the V&R is really bad now, as if something is getting ready to fall off! Dad is feeling really stupid and bad about this!

Thanks, any ideas welcome............

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744 & 745 GLE's (IPD a-sbars)16v M46, 245 SE(IPD a-sbars) auto, 242Ti M46(IPD springs and bars), 745GL 8v auto