cliffdiver96

Hey guys I just installed a RC 3in series II lift and got some vibrations from about 45-60mph.

I was told to pick up some 2* degree shims and that should fix the vibration.

Well I was also looking into doing some H.D Offroad shackle relocation kit brackets and possibly some longer RC shackles and was wondering if that would fix the vibrations instead of doing the shims, anyone have any input or advice on this?

Thanks

91XJBlackonBlack

do you have an sye, or transfer case drop? If not it could be your u-joint. Thats what most vibrations are caused by when lifting your xj.

cliffdiver96

No sye-(wanted to see if the shackle relocation would fix it first) and I was leaning away from the transfer case drop because its only a 3in lift so i dont have a whole lot of ground clearance to work with

Ill definitely look into changing the u-joints though, thanks

xjheep92

Hack n tap runs about $100 bucks
And with shims is the cheapest best way to go

Lead Foot

By adding a Standard Shackle Relocation Kit and/or extended shackles you will essentially drop down the back of the leaf springs like you figured which may give you that 2 degrees adjustment on the pinion angle that someone suggested. I'm assuming this suggestion was made by someone who saw the rig and inspected the driveline angles theirself?

Dont forget that we sell our Shackle Relocation kits along with Nut Strips and Bolts for an unbeatable price. Use Cherokeeforum as a discount code to get 10% off upon checkout. These are in stock and ready to ship.

Kris Froehlich

HudsonN

Generally speaking the degree of shims you need matches the amount of lift you put on.

2 inches = 2 degree shim.

4 inches = 4 degree shim.

cliffdiver96

I was told to go with the 2 degree shims from the guys that installed the lift, and the owner of the local performance/offroad parts store.

Ill definitely check out your shackle relocation brackets you offer Lead foot

still_alive

Just an extended shackle itself may be enough to cure your vibrations. I run 4.5" lift with no transfer case drop, no shims, just a small shackle and it rides smooth as butter. It's all in how much time you wanna play with it to get it right. You just gotta try stuff to see if it helps or not.

bighouts5591

I've always been told that without a SYE you don't want to add shims. With a slip yoke style driveshaft like our stock XJ rear, you want the yokes on the diff and the t-case to be parallel. However, with a double cardan joint like the front, you will want the diff yoke to point at the t-case. A 1" t-case drop will most likely fix your issues, and its by far the cheapest and easiest solution. U-joints may cause it too, but normally you'll hear them chirping at low speed as well.

xjheep92

This ^
I thought the same

Lead Foot

I agree. Thats what I would normally suggest. I based the opinion I made off what (hopefully) an experienced offroad alignment tech told him.

Falon

We still have a ton of these in stock at awesome prices.

rex21

You have one less of those kits in stock. Mine is on the way.

To the OP, you should either just do the t-case drop, or an SYE and shims.
A t-case drop can be self made very easily, just do some reading and look at the pictures. I made mine for about $4 in bolts and some aluminum I had.
If you are not handy, then just buy one, they are not too expensive.

Don't rule out bad u-joints though, your new driveshaft angles can multiply the effects of a joint that was marginal before the lift.

cliffdiver96

Sorry for the delay, i just put 35x12.5 Mickey Thompsons on it with the 3in lift and spent most of the week trimming and massaging the fenders with a 5lb sledge hammer so they dont rub.

Im going to be ordering up a set from you guys in the next couple days. Just trying to decide whether to go with the no lift or the original version. I want to keep it at 3.5-4inches of lift tops, soo im thinking maybe go with the no lift version and find a small shackle?

As far as the vibration I found the transmission is going, soo im going to have it rebuilt and have the tranny shop add an sye whilst its there.

Thanks for all the help guys!!