My car seems to have grown a vibration recently. When on the highway, usualy running in 5th gear at low revs the car will vibrate with my foot on the gas. Whenever I take my foot off the go pedal, the vibration stops. It seems to only do it at low revs. If I shift to 4th the vibration goes away until I let the revs get below about 3500. I am thinking the drive-shaft may be causing the vibration, or maybe a particular mount. Does anyone have any suggestions on what it may be?

 

Pull of your driveshaft and inspect the u-joints at the end of the driveshaft that is closest to the tranny. I had a problem like that once.

 

Yeah check the u-joints and make sure that they arent seized or aboot to seize.
If when your not moving and you rev the engine and it vibrates like before, then your engine mounts are toast. My car is doing this right now, vibrating at low rpm's even while not moving, so I will be replacing my engine mounts.

 

Yeah, check those well... You don't want your driveshaft falling from the front and comming out flying thru your roof !!!

 

What exactly should I be looking for on the drive shaft? I mean, I know what the U-joints are, but what would be wrong with them? Will it be obvious? Do I need to remove the drive shaft to inspect it?

 

Try turning it by hand there sould be a little play but not a lot. Turn it back and forward and if you hear any banging they should be replaced. Those are cheap and easy to change.

 

Your driveshaft will vibrate according to speed of the vehicle, not engine RPM. Maybe bad engine mounts or there might be something wrong with the A/F mixture.

Cheers

 

Actually, you can have driveshaft vibration that is load dependent.