Drive Train Vibration

[senrab]

Let me start by saying thanks to everyone who helps the rest of us. I've learned a lot and fixed multiple problems over several years.
2000 Regal 3.8 w SC 140k
My problem is I have a vibration that is only present if you are accelerating or driving at a steady speed. I had a CV joint that had blown all the grease and replaced it. Had a bad tie rod on the CV side (passenger) and replaced it when I did the axle. Replaced a rear hub bearing that had a bad speed sensor and made the dash light up like christmas (ABS, TCS & Service E Soon). Checked all the other wheels, hubs and tie rods = OK.

This vibration is never there if you're coasting regardless of any direction turned and is always present when driving straight as well as turns when accelerating. It is constant if in cruise on a level road but intensifies when acclerating. Because of the way it reacts to the power I think it is drive train related and not the rear. It does not change with shifts so I don't think it's tranny related. I've read every thread I can find and been around the car several times. This vibration seems to be a common problem with several cures and opinions.

Could a mount cause this?
The other CV feels tight but how do I check to be sure? It's not leaking grease.
Would the struts cause this only on accel?
Control arm bushings? How do I check?

Sorry for all the questions.

[BNaylor]

If you have the original struts then thats a possibility. The originals start wearing out at around 70K miles. Also, if original front hub/wheel bearings. How old are the tires and the wheel balance?

[senrab]

Not sure how old the struts are. My son bought this and has had it at college. He has put around 45 k on it and is the second owner. The first owner took good care of the car and had a dealership do all the service. What all was done I'm not sure but my son moved to a big city and I bought the car from him since he can't afford a parking spot. As for the hubs, I've looked, shook and ohm tested all and replaced one. I had an Aurora and had to replace both fronts. With that car I had the typical whineing / road noise that increased as the bearing got worse. But this isn't noisy like that was. I know it still maybe a hub, but didn't want to just throw money / parts at a problem unless the parts were bad. Is there anyway to check the struts for wear by measuring deflection or something else.
The tires have about 20k and probably need rebalanced and rotated. They don't show signs of cupping or other abnormal wear but I may start there as it needs done and is relatively inexpensive. It really doesn't act like bad balance because usually tires seem to smooth out at certain speeds. This stays steady but increases the itensity and tempo as the speed increases.

Update for others searching similar problems.

Replaced the other axle / CV that was not leaking grease and the vibration disappeared.

Thanks to everyones help in this and the other threads I read.