I did all the changes during rear engine oil seal and transmission oil seal replacement. At 182K and 13 years, I figured it was time to replace the u-joints and support bearing/bushing while I had it all apart anyway. The vibration/rumble occurs during acceleration, deceleration, and coasting. There is one "phase" of vibration at about 25-28 mph, and then again at about 45-60 mph. At 25-28 mph it is more of a noticable vibration (even the steering wheel shakes) whereas at 45-60 mph is a a very low resonating rumble.

I have "shimmed" the center bearing successfully on another car, but the symtom in that case was vibration accelerating from a dead stop (0-15 mph). This car has absolutely no vibration or rumbling while accelerating from a dead stop.

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Matt L. -- Cary, NC -- two '89 740 sedans and a '91 740 wagon