tj rear vibration.

[69jeepcj]

A friends brother just got a 2000 tj 4cyl which he says has a 6inch lift not sure of tire size, probably 33-35". I haven't seen it yet, but he says it has a bad vibration from the rear when you accelerate. It does have a tcase drop, and I think adjustable control arms as my friend said he can adjust the suspension at each corner, (he just thought that was so cool, lol). where do I begin to look for this issue? I was thinking SYE kit would be a possible fix?? As I said, I haven't even seen the jeep yet so im just going by what my friend told me about it. Thanks for any insight

 

[wwch99tj]

If it doesn't have a sye yet that'll be where to start

 

[Bounty__Hunter]

Make sure the rear axle pinion is parallel with the transfer case output if no SYE is instslled.

The front pinion angle will be a compromise between being in line with the driveshaft and having correct caster.

 

[69jeepcj]

If pinion angles are off do the adjustable control arms change that? Do you think a SYE could cure it if the angles cant be corrected with the control arms? Hate asking these questions, but I really know nothing about the coil spring, 4link set ups. Thanks

 

[JPNinPA]

Without SYE

When you get the SYE
http://www.stu-offroad.com/axle/pinion/pinion-1.htm

 

[69jeepcj]

JPNinPA, was there a link that went with the "Without SYE"? and thanks for the other link. I got to see the jeep yesterday, its pretty nice. He does have adjustable lower arms but I cant remember if there were upper adjustables or not. He has never had a jeep before and said he absolutely loves that thing, so I want to try and solve this issue so maybe he will keep it and I will have a jeepin buddy, lol. Oh, there is not a SYE on the jeep now

 

[JPNinPA]

JPNinPA, was there a link that went with the "Without SYE"? and thanks for the other link. I got to see the jeep yesterday, its pretty nice. He does have adjustable lower arms but I cant remember if there were upper adjustables or not. He has never had a jeep before and said he absolutely loves that thing, so I want to try and solve this issue so maybe he will keep it and I will have a jeepin buddy, lol. Oh, there is not a SYE on the jeep now

Updated with video. I thought I had another link from stu or someone else off a forum but I can't find it. If you had a engine mount lift and skid plate drop with a thin trans mount this would change the transfer case angle giving a bit more adjustment. IIRC four or more inches of lift a SYE is definitely needed mostly to eliminate dropping the drive shaft when the suspension flexes.

 

[69jeepcj]

Do you need a new driveshaft with the SYE, we were talking yesterday and he wondered about that. Thanks!

 

[eric m]

Do you need a new driveshaft with the SYE, we were talking yesterday and he wondered about that. Thanks!

Yes you do.

 

[NewEnglandXJ]

Was wondering if there is anyone from Massachusetts here?

 

[JPNinPA]

Look under the local jeep boards. There are a few but posts appear older. Still some may be lurking without posting.

 

[NewEnglandXJ]

Ok thank you.