'03 Pathfinder SE-Vibration/shudder feel at all speeds

[Pathfound49]

Had it to a garage that said u-joints, drive shaft, front cv axles are fine. He said he poured in an anti-shudder treatment for the torque converter, but it changed nothing.

Tried the old overdrive turned off trick so the TC doesn't lock up, still no change.

Had a friend say the u-joints could be shot without having a loose feel when underneath the truck.

Any other comments/suggestions are welcome. Oh. And it gets more pronounced under mid/heavy acceleration.

[Infinitiguy19]

I would say U-joint too but I wouldn't rule out the engine or transmission mounts.

[Pathfound49]

After further inspection by a mechanic friend, the front u-joint has a very small amount of movement to it. As the vibration is not excessive at this time, I'm assuming it is at the early stages of going out.

[Pat Connelly]

You are correct. I would replace it soon, as the vibration could cause other problems with bushings, causing leaky seals, etc. I just replaced all 4 U-joints on my '97 QX4 and it's a pretty easy job. Also check your ball joints for wear.

[Pathfound49]

Update on the u-joints. Had both the front and rear drive shafts out to inspect the u-joints. There is no looseness, binding, or clicking in any of them. At this point it is going to a trans shop to get looked at. The dealer gave me a 4500 mi. powertrain warranty on it and I'm gonna use it.

It must be internal at this point.

[Pathfound49]

OK guys. Here's one for you. I just replaced all 4 u-joints on my truck. Put the drive shafts back in and took it for a ride. There is now a steady vibration when off the gas and on. Gets worse over 2000 rpm. This has been steadily getting worse up to and before the u-joint change. Vibration under heavy acceleration is minimal as opposed to before the change.

Question. Does anyone know the importance of alignment of the drive shafts and the end yokes? I marked them prior to the u-joint swap, but PB Blaster and greasy hands wore off the markings.

Any help would be appreciated to no end.
Modified by Pathfound49 at 5:03 PM 4/1/2010

[Pathfound49]

Update #2. Just rotated the rear drive shaft 180 degrees to see if it changed things. Test drive=NOPE!!! I am at a loss here. The $$$ tag seems to be heading for the moon.

[Pathfound49]

Just pulled front drive shaft and took a test ride. Vibration/shudder is gone. Sorry for all the updates. Just want to pass along as much info as I can in case anyone has/had the same issue, but with a known solution.