[doubleroost]

I took the 2 inch lift shackles off and dropped it down to 1 inch shackles. I put tires on that i know are good... It still shakes when the driveline has torque on it. the u joints have like 500 miles on them and they're tight. I still can't figure this out.. any ideas? Could a worn out rear do something like that? If the pinnion has play in it?

[Lumpymayo]

Do you have a SYE?

[doubleroost]

No but I only have 1 inch of suspension lift. Would 1 inch have that much of an effect?

[jeepinbowhunter]

I have an 1 1/2" Shackle lift and I don't get any vibration. I just had a vibration that occurred only durring accel. and I replaced the U-joints and it's smooth now. One of the responses I had was to check and replace the rear oil seal and bushing on the transfer case tail shaft. If your U-joints were really bad it could have wallowed out that bushing in the tail shaft cone. If it did you should be leaking T-case fluid and be able to see where it has been slung up under the tub just above the front U-joint on the rear drive shaft.

Your tires are balanced? But if it was a tire I would think you would have it regardless of whether the drive line was engaged or not. There is a thread on replacing the bushing in hte FAQ iI believe.

[doubleroost]

Does that symptom look like this. I have fluid being thrown onto my muffler.



I do have play where the slip yoke rides the tail shaft but I don't think replacing that seal will fix that... will it?

[jeepinbowhunter]

I would definitely check the t-case fluid level asap. If you run out of fluid that would be a very bad thing It looks like you have a really heavy leak there. There will be a little play on the shaft but very little. You have a lot more leakage than I did. Look at post #4 in the faq section. That should answer a lot of your question. With out being there, I can't give you a yes or no if that will solve your question.

[pat8942]

That looks more like grease being slung on the muffler from the u-joint.
It's right in line with the joint and mine has the same mark and the t-case doesn't leak.
Right after I grease my joints the excess grease gets slung on the muffler and I'll bet every YJ that gets the U-Joints greased has the same mark.

Originally Posted by doubleroost

Does that symptom look like this. I have fluid being thrown onto my muffler.



I do have play where the slip yoke rides the tail shaft but I don't think replacing that seal will fix that... will it?

[jcook1989]

Sounds like you might have some worn out U joints in your rear driveshaft. Get underneath and play around with the driveshaft if it has some play in it then its your U joints. Just pull the shaft. Go buy some new joints and install them. I had the same problem and it cost about $40 to get it fixed $20 for the joints and $20 to get them pressed in.

[doubleroost]

The joints as I explained above are brand new and tight so thats not it.

[doubleroost]

This isn't an actually vibration coming from the driveshaft... it's like the whole jeep shimmys and shakes when you have it in gear, its the worst going between 31-35 mph. I'm missing one of my rear shocks and one of my sway bar brackets are broken, I'm thinking now that maybe these are playing a part in the problem. I'll have to put the shock back on and see if that does anything for me.