I feel your pain elwesso, I'm in the process of coming the grim conclusion that I might be having driveshaft issues with my 240. I found out that I had a wasted rear wheel bearing about the same my car started to vibrate, so I happened to have a spare wheel bearing and hub laying around, with suposedly 60k mi on it , anyway needless to say it still blown. In the process of replacing the bearing/hub assembly I noticed that my sub-frame bushings are bleeding all over the place, so now i'm thinking well maybe the vibrations coming from the subframe... so I get on the trusty old interweb and order anew wheel bearing and SPL bushing collars, all to be installed this weekend (crosses fingers). Then I come across your post and you get me thinking so I grab my jack and put the rear end up, get in and start accelerating through third gear until I start feeling the vibration, which begins to occur at 30mph, the rear wheel that has the bad bearing doesnt shake or appear to be causing the vibration so know I'm thinking hey maybe it's worse than I thought and my stomachs turning! You got one thing right though, it is a bittersweet relationship we have with our cars at times.
So know I'm hoping that this statement is true for me;
FarFetched wrote:If yo have vibes at 30-40 MPH that is torque twist (rear sust subframe bushings are going bye-bye)
Anyway good luck!B