If it's for short distances and not for an extended period of time it won't be a problem. I drove my Cherokee for a week to and from work with no ill effects.

 

They were mentioned. See #1 on the list in post #11. Don't know if he checked them or not.

In any event his issue doesn't sound like DW.

 

I guess. I still wouldn't recommed it. But, if you do, just make sure to be easy on the gas. Don't try to whip it around

 

As far as the ball joints go I did check them and they were tight. Reguarless I think I can lay the DW idea to rest for at least right now. I was doing some reasearch on pinion angles and found that if the transfer case and the rear end arn't parallel to each other than they won't share the vibration 50/50 and lead twords an harmonic balance issue. This being said there is a t-case drop causing the t-case to be at a different angle than the rear end. (follow me so far?) So I figure that I would either have to remove the drop or add a shim in the rear to make them parallel to each other........ Any thoughts?

 

That will work IF it is the rear causing the vibs. It will be a lot easier to remove the front driveshaft and see if that takes care of the vibs. If it does, great...you know its withing the front driveshaft. If not, still great, you know it's not the front and then you and move to the rear.

 

If you think this is actually a rear driveshaft vibration and not death wobble then there are a few things to check. First would be motor mounts. Yes, motor mounts. The driver's side in particular. Then the transmission mount. Then move on to figuring out the angles. On a single u-joint drive shaft the angles should be equal but opposite under load. Meaning that if the output shaft of the transfer case is pointing down at lets say 7* then your pinion should be pointing up at 7* when you are driving down the road. Being that the XJ has leaf springs in the rear and you are always going to get a little bit of spring wrap a 2-3* difference at rest is good. It's OK to have the pinion a little lower than the transfer case output shaft when the Jeep is at rest. Generally a 4* or 6* shim will work for a CV style drive shaft and no T-case drop. If you have a T-case drop and a stock drive shaft then a 2.5* shim should be fine.

How many miles on the Jeep? Could also be a slip yoke that is pulled out to far/worn out.

 

Well I "think" I may have found the problem. I've said that twenty times now and have been right that it was a problem but wrong that it wasn't the problem I was trying to fix. So lets hope this is it this time.

I took out the Transfer case drop and put it back to stock settings. It lessened the vibration a little. So we are in the right area if it made a difference. After I got back from the test drive I went back underneath to take another look. I found that the front driveshaft, front U-joint was really loose. I know for sure that I checked this at least twice before and it was tight. I don't know if the change in angle loosened a bind or what.

All I know is that I'm putting a new one in tomorrow and hoping this fixes it so I can start working on other things like accessories and stuff. We'll find out tomorrow. Man I'm going to feel really stupid and happy all at the same time if its the problem. I can't believe I would miss something like that. I'm not a expert but I'm not a newbe either.I'll let you guys know tomorrow if I fixed it or not.

 

Good luck!!

 

shoot shoot shoot shoot shoot , The U-joint was fine. The peice that bolts in to hold the U-joint was loose on the ends witch let it slide a little to make is seem like the U-joint was bad. I put a small washer in the end to fill the gap witch tightened it up. Went for a test drive and it still didn't help even a little bit. I even greased up the slip yoke alot to make sure there wasn't any play.

On top of all that my front brake caliper seems to be leaking fluid after I just checked it when I did the brakes a couple days ago. And the engine is blowing white smoke out the tail pipe after sitting over night (I guess thats where my antifreeze is going thats missing). But screw all that, I just want rid off this damn vibration.

So Now What????????

 

Now I took out the front drive shaft. The vibration before occured weather it was in drive or not. Now the more that I give it gas or if I'm going up a hill it will vibrate. In N or gliding down a hill it dosen't vibrate. Are we getting anywhere yet?

 

Check those motor mounts and transmission mount.

 

Tranny mount and Passenger Motor mounts are good. Drivers side probably could be replaced but its not terrible. Getting vibrations at low speeds now. I think the yoke is slipping out too far since I took off the t-case drop. I'm going to put it back on to drop the t-case back down and order a 2-3 degree shim. I'm thinking of swapping the driveshaft off of my other Jeep that I'm about ready to sell. It dosen't have any vibration problems just a lot of rust.

 

Ok, So I took your advice about the motor mount and picked one up yesterday for the drivers side. I also picked up some shims for the rear end and some new U bolts since I have had a clunk noise in the rear end. I plan on installing all that today and putting the t-case drop back in.

Yesterday I took off the rear drive shaft. The slip yoke was rusted pretty bad. I put some penitrating oil on it and greased it up. And I put a new Rear U-joint in since it was a little stiff. Took it for a test drive. Still no difference.

 

**UPDATE**

I shimmed the rear end to 2* and changed the T-case drop from 1 1/2" to a 1" drop. The pinion angles are a better. Took it for a test drive and it got rid of 95% of the vibration. Thats the good news. The bad news is that when I put the front drive shaft back in it started to vibrate again. I figure its the same problem that the rear had with the pinion angles. Question is how to I adjust the pinion angle. I tried sliding the LCAs to change the caster but it would only go so far. How can I slide if further? There is more slot but it won't let me go any farther forward.

 

Slip Yoke Eliminator will get rid of the bad angles on the front shaft along with at least one set of adjustable control arms.