After lifting my Jeep 3.5" I started getting vibrations.
I replaced the rear U joints to try cut them out, no luck.
Took out the front drive shaft, still vibes.
Solution is going to have to be a SYE.

TLDR Problem:
I'm getting a harsh grinding\groaning sound from under my feet under deceleration or coasting.

I did a video so you guys can watch and tell me.

I read up on this and think I'm getting chain slap or it's my U joints...that are new. I really just want to be done with all the problems my Jeep is throwing at me so I can enjoy just driving around.







?

 

im having a similar issue that i cant seem to track down

 

I have wiggled the yolks and they don't move around like they are worn out. I have read to check that and that it could be the chain inside the transfer case hitting the inside of the case as well.

I guess that after all this reading, I'm looking for someone that has experienced the same thing so that I can buy the right parts.

Since I'll be putting on an SYE I figured I could replace some of the worn out internals of the transfer case while it'll be apart. I'll be paying a local company to rebuild it after I take it off, as I don't possess the press needed unfortunately.

If there's a member in the southeast near me with one....case of beer? Root beer if you don't drink...Whatever.

I'm keeping my posts to a minimum and will be following up this one as well as my previous posts about my steering issue...

 

you could simply just do a 1 inch transfer case drop by using spacers in between the cross member and frame to see if that takes care of vibes.
the angle could just be a bit too steep for the yokes to run smooth.

but all in all, a slip yoke eliminator is best idea, and you don't loose that inch of clearance. but you will need a new rear drive shaft made up. some guys use a front drive shaft out of a 4.0L auto xj. you may have to get it shortened, you may not... i would use a tom woods shaft, myself.

 

I want to know what the noise is. I'm rebuilding the case and was wondering if this is chain slap....I got off topic.

 

I had this same noise not too long ago. My rubicon express 3.5 actually lifted the rear 5.5. I installed an SYE and temporarily moved my front driveshaft to the rear while waiting for my new shaft to arrive. I got the same noise when lifting off the throttle, no load. It was a combination of loose splines on the driveshaft and incorrect pinion angle. I shimmed the rear axle ti fix the pinion angle and it improved. With the new driveshaft the noise is gone. You are correct to install the SYE, and a new driveshaft and axle shims go hand in hand with it. That will most likely take care of any vibrations/noise.

 

An SYE with shims should cure most of this problem. When I had my SYE installed I also replaced my TC chain as it was loose after 230,000 mi.


A TC drop kit is just a Band-Aid for an SYE and not a very good one at that, as they cause issues themselves.

 

Hey I'm having this exact problem can you please tell me if I could cut the chain or remove the transfer case beings I took the front drive shaft off for the 4x4

 

Sye or shim the rear or both. The front driveshaft has nothing to do with the vibes.

I always start with fresh u joints after a lift if it still vibes and groans on deceleration and acceleration then I add shims. If it's still there which it usually isn't then a SYE and new shaft is next step. While your doing the tcase swap you can evaluate your chain.

Tcase drops shouldn't even be an option

I'd go with a hack in tap $99 and a used front drive shaft before a tcase drop if your funds are limited. 4.5 lift and under I've had good luck with new u joint and 4° axle shims. May still have slight vibes but will get you around and on the trail while saving for a SYE.

 

No, can't do either. The transfer case is connected to the transmission and sends power to both front and rear shafts.

If you have vibrations without the front driveshaft, then it is probably your rear driveshaft causing the issue. Look into a transfer case drop. Would be the best way since obviously you aren't concerned with ground clearance if you already neutered your jeep.

 

Mine did the same thing after I lifted it without the SYE. Once I put the SYE in, no more noise. I want to say it has something to do with the slip-yoke being out farther out on the splines which is where the noise comes from. I'm not 100% on this but I do know that an SYE takes care of it.