RE 3.5 lift, and general vibration

[ntrsvic]

I read through this post, http://www.naxja.org/forum/showthread.php?t=915565 , a bunch and I have some questions.

I just finished lifting my XJ 3.5 inches and now I need to stop the vibration when I drive.

The car is at an angle because the rear is lifted more the front..

So, I have to set the pinion coming out of the transfer case as 0°. I don't have a CV drive shaft. I think that should be noted. Now, I need make it so that my differential is also at a 0° angle and the Resulting angle down from the transfer case to the drive shaft is the same as the angle up from the differential to the drive shaft?

Is this correct?

IF so, where should I measure on the XJ after finding the flattest piece of ground around?

Lastly, at what point is this angle to extreme and I should consider getting a 1 or 2in drop for my transfer case? (Which would of course change the plane of my pinion coming out of my transfer case).


Thanks guys.

 

[lancey3]

get a tc drop

 

[newjeepowner]

get a tc drop

X2

 

[DJH87xj]

w/o a cv driveline one way you can check angle is put the slip yoke in the tc @ 12 and 6 same with pinion measure the top then the bottom..if your within 1/8 in your good if not you need to shim the rearend. I have an 87 with 5.5 in lift and just built a cv dl and didnt need to drop the tc..hope that helps

 

[XJ_99]

I have the RE 3.5 SF kit with a t-case drop and I am vib free......

 

[ntrsvic]

I have the RE 3.5 SF kit with a t-case drop and I am vib free......

Ya, I just crawled under there again with my friend who helped me put it on. Our opinion matched that of the guy who did the allignment. The angle is much worse between the Pinnion and the drive shaft..

TC drop seems the way to go. I assume 2 in.

 

[newjeepowner]

2 inches will make a difference

 

[gijosiahh]

another question... is it pointless to get a tcase drop and add shims?

 

[XbajajeepX]

If you're going to do a Tcase drop, only go 1"...

 

[ZacSquatch]

never seen a 2" tc drop.. might be kinda goofy... if anything, 1" and maybe 3* shims at the most

 

[cal]

Yeah, do not try and drop your TC 2". The engine, transmission and transfercase are one assembly, and dropping the TC points the engine up and so on. it puts stress on your motor mounts, exhaust manifold (the exhaust manifold is forced to change angle, but the exhaust it bolts to does not, creating stress and leading to cracks), etc.

You can usually get away with a 1" TC drop, but you are just that - getting away with it. Trying to do more would be foolish and lead to trouble.

Try 1", if you cant get the angles close with that, do an SYE and CV driveshaft.

 

[gijosiahh]

so it wouldn't be too wise to do a 1" drop AND add shims?

 

[lamula]

I did a 4.5 inch R.E. lift on mine and used the 3/4" t.c. drop. After it was on the ground I needed 4*of shim and It worked great! Try to get the steel shims rather than the aluminum, I think they are stronger. I couldnt use much more than a 3/4" drop as it would screw up the trans linkage alignment.
T.C. drop and shims are ok, and cheep, SYE and CV shaft are better, much more expensive.

 

[AlarminXJ]

If you are going to do the t-case drop, one option, rather than just the spacer kit, is Rusty's T-Case cross-member with built-in drop. This is pretty cool, because it does not loose you any ground clearance, the drop is achieved by the internal shape of the top of the cross-member. It is also way thicker/ stronger than the stock one, and serves as another skid plate. It is a little more expensive than just a spacer drop, but it was worth it for me to save the ground clearance.

 

[cal]

so it wouldn't be too wise to do a 1" drop AND add shims?

The two technically have nothing to do with each other, but yes, you may (unlikely) find it necessary to do both. Look at the angle of the rear pinion in relation to the driveshaft, and the angle of the output shaft on the transfer case, in relation to the driveshaft. They should be the same - transfer case drop lessens the upper, shims lessen the lower. In some situations, you may find it beneficial to lesson both, but without a lot of lift, just getting them to the same relative angle will be enough.

 

[lancey3]

The stock cross member can take a beating. And in his situation IMHO I see no need for him to buy the Rusty's T-Case cross-member with built-in drop.