miglia-spyder

Just lifted my 00' xj with an RC 4.5" and I have a couple vibrations. So i had it aligned yesterday. I drove it around all day just listening and feeling for vibrations... The noise/vibration i have now and had before was coming from the front drive shaft, because when i took it off the noise/vibration went away. Now the rear driveshaft is starting to vibrate quite a bit and make a loose sound when i let off the gas or brake. None of the U-joints were bad before (not that I could tell anyway), could they be bad now because of the different angles?
Oh by the way, My kit did come with a t-case drop, which i did install.
Should i just replace all the U-joints?
Why would the front drive shaft be binding? The pinion angle looks fine in the front...


Sorry for my stupidity guys... Im new to these straight axle vehicles, Im used to lowering sports cars and adjusting camber angles...

93gc40

On the rear, Is your pinion angle good? you may need to add a shim to the axel to correct. TC drop and shims, is a bandaid step to correcting driveline vibes. You might need to look into a SYE kit.

TC drop do work up to 3.5" of lift but after that it can be hit and miss. Dropping the TC cam improve angles for the rear end, but makes them worse in the front at the same time.

miglia-spyder

yeah i plan on getting an SYE but thats another 500 bones with a new drive shaft... So its gonna be a while.

BuckB91XJ

Miglia, I don't believe you have any rear U-joint problems. If like you say there were no noises in your rear driveshaft and there are now, it's most likely due to the fact that your rear driveshaft slip yoke is extended outside the TC a bit now after the lift. This can cause the noise you speak of when getting on the gas or letting off. While not as huge issue if you're used to no noise being there. Then you would definitely hear it now. Just not as much of your slip yoke spline area is meshed with the TC splines. The drop kit for your TC will help the angles caused by your lift and get rid of the vibes but, you will still hear a little bit of additional noise after a lift. The SYE will cure this problem.

miglia-spyder

That makes sense... I can see that making this noise.

Thanks

93gc40

You should look at a HackNTap SYE and using a Front driveshaft from a JunkYard. Could solve the problem for $200 or less. Search on SYE, there are less expensive options.

01LimitedXJ

there are many options out there, and quite a few of the heavy duty ones will allow you to run the same driveshaft front and rear. 4.5 inches of lift, you DEF need a SYE on a newer model XJ.

miglia-spyder

I would love to be able to run a front drive shaft in the rear... that would save me some money until i can get a new rear shaft...

I was looking into the PORC SYE but i have been hearing that its a nice product but they're cutomer service is on the weak side.

What SYE's could i use with the front D/S? Does it just depend on the output yoke size?

01LimitedXJ

Thats what i got. Ive always had a good experience buying from them...they even called me right after i ordered one to confirm, and tell me it would ship out to my house in like 4 days.

Advanced Adapters and PORC are 2 right off the top of my head...