Any luck getting this fixed. Mine has 133K on it. Once I go to 5th a high speed rotational vibration is felt in the seat. More so under load. It still vibrates coasting but not as bad. I believe it is the U joints. All of the harmonics of the drive train align and make the vibration more noticeable at that speed. I did the wiggle and shake test and lubed them. No change at all. I know the wiggle test is not 100%. Due to the age and mileage and prior maintenace by PO I'm sure the U joints are due for a change.

 

The best way to check the u-joints is to pull the driveline down and rotate the joint around feeling for stiffness and roughness of movement. Might just have to break down and do that, Alan. I know.......what fun, eh? You probably know this, but if the needle bearings are toast, no amount of grease will make them float smooth again.

 

Ya it was the trans. I swapped it out and all good. Input bearing was getting sloppy.
Yours sounds like something else though because if I let off the throttle or coast it would stop. Only vibrate under light load at highway speed.

Check your cross-member mount. I had a 4runner that would get a vibration like you describe and it was the rubber in the mount had pulled away from the steel.

 

Yeah, I had a few minutes at work today I decided to check the u joints just to make sure they weren't fixin' to explode. I'll break it down and check them out. I hate changing U joints. I usually loose my religion. HAHA

I hope your right. I much rather change U joints than and tranny. Which reminds me. When I first roll in the morning it feels like the clutch is jittery when engaging. But fine the rest of the time.

 

Does this mean if you had no religion you'd have nothing to lose? Bahahaha!....


........okay, bad joke.

 

OK pulled the drive shaft and checked the U joints. Everything is tight and smooth. The drive shaft looks to be in phase. Over the years during maintenance someone marked the drive shaft to flange with a punch mark and all is still lined up. I want to drain and refill the tranny and xfer case. BTW I installed locking hubs on the front about a month ago so I can disengage the front. So that won't be a factor.