Just had Truetrac installed, now feel pulsing vibration when driving?

My money is on Ujoints. Sometimes when they are old and you remove Driveshaft they tend to fall appart (lose needles) Check uJoints and if they are old I would get somebody to replace it. since your DS is already out of the truck

 

I'll bring it up

 

I've never heard mine screech, but I'm not certain if I've ever lifted one wheel completely off the ground. I have very grippy AT tires, and when I wheel, I air down. Its very rare that my tires slip at all, but then I don't do the Rubicon with this rig either (at least not yet anyway).

 

Yeah it was a weird noise. But I did get out fine with the e-brake trick

 

So I got under the truck and was checking my u-joints for play, and they are tight, no play. But my center bearing seems to have a lot of play. Like 1/4", a little less maybe. That's probably my problem, but I still don't get why I've never felt anything before the Truetrac install. The vibes are pretty noticeable. I have a video of me shaking the bearing, am I'll try to get it up later

 

Btw guys, just got my truck back from the transmission shop. They rotated the driveshaft 180 and no vibes now . He also greased my u joints which was nice. I also asked him about the center bearing. He thought it had a little play in the rubber, but he wouldn't replace it yet. That it's going to need it eventually but it's still got some life. Thanks for the help!

 

Glad thats finally over. Thanx for getting back with the solution.

 

Thanks for your help. It's weird cause the alignment marks on the driveshaft and carrier flange lined up, so I assume they put it back together how it came apart. But I guess they didn't

 

Oh and thanks for the truetrac recommendation tan4x4 on my thread awhile back. I love it. I have noticed that sometimes it likes to act like a spool on wet or sand road and chirps, but nothing bad. Actually I tries to get a little drift going yesterday in the rain and it won't let me. I did better drifting with the open diff haha

 

Vibes are still there. Better but still there. Back to the drawing board, might check out a drive shaft shop. Still don't understand why it wasn't vibrating till after the truetrac install

 

Damn !

Well, its possible that the problem happened coincidentally with the TT install. I just re-read your early post about there being about a half-second between each 'pulse' at 45mph. If the drive train were to cause a problem, the pulse would be more of a shimmy (maybe 8 times per second ?).

Next time you are in the shop, have the 3 motor mounts checked. Maybe one is loose or cracked.

 

It does kind a pulse like you said. It's a real quick vibration every half second maybe, from about 40-55 mph. Idk if they checked motor mounts, I know he checked trans mount and it was a little dry rotted, but otherwise ok. My center bearing has some play in the rubber but he wasn't too concerned about that. I'll put that video up later and see what you guys think. What's weird is it is better since he rotated the driveshaft, it was almost non-existent, and now it's back. He did grease my u-joints. Maybe one of them are bad and the grease covered it up for a while. I can't shake any of my u-joints loose

 

These are probably factory u-joints. 162k on them

 

I'm a second gen but I have also experienced this "screech" from my truetrac in an off camber situation. Methinks that its just the internal gears rubbing against the differential case (just the nature of how this diff works). And because one tire is in the air and spinning relatively fast the metal to metal contact within the diff to slow that tire down is causing that screeching sound. When I first heard it I was a bit scared but I've been able to replicate it every time I lift a tire so I just take it as its just the LSD doing its job. So far I have seen no negative impacts and in those situations, I just use a touch of brakes to engage the LSD and get out every time.

 

I contacted Eaton about the noise and they said it was normal

 

what is this "ebrake trick" you speak of?

 

Apply a bit of ebrake and it’ll provide just enough resistance for the Truetrac to transfer power to the wheel on the ground.