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Vibes after 1" lift, what to do??

If I have to remove my center bolt and use a longer one, I'm probably better off going with steel shims than aluminum then, right? Or don't they make 2.5* shims in steel? If that's the case, where do I get center bolts from. What size are they, what thread pitch, and what length? I know nothing about shims and/or replacing a center bolt from a leaf spring pack, so I need to know everything I need to get/do.

Or is it just a matter of removing the center bolt, and reinstalling it after putting in the shim? A 2.5* shim can't be that thick, maybe I can reuse my center bolt that cam in my Quadratec HD leaf springs. I really don't know though.
 
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Not too thick, get steel, not aluminum. Just clamp it tight, take it out, put the shim under it and reverse.
 
Alright, so I can indeed use the same center bolt?

I found a place that makes steel shims in pretty much any degree.

http://www.rocky-road.com/jeepshim.html

If I get the 2 degree shims from those guys, I will still be able to use my existing center bolt? I assume I'll want to go with the 2.5" wide shims. Which way should I insert the shim. Fat end toward the front of the vehicle, or fat end toward the rear of the vehicle?
 
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with the shims I used I just loosened not removed the u-bolt, the hole was big enough for the pin to fit thru & the shim was thin enough for the pin to seat in the perch. and yes I agree the 2.5 degree shim is the one to use but I couldn't find the p.n. for the 2 & 1/2" shim,only the 2" & a 3".try www.jackit.com. I know they exist because I was going to use them untill I found out the pro comp 2 & 1/2" springs we were using came with a built in shim. jack-it has an 888# it's 888-4-jackit.sorry I didn't answer private message-net glitch. good luck
 
you can't reuse center bolts but offroad shops and spring shops will have them. I've heard of people using socket heads or grinding the head round on regular grade 8s to fit in the perch. I always cut the excess bolt off almost flush with the nut. If you don't use real spring bolts make sure to use quality hardware
 
I called the guys at JackIt and they told me I need to measure the angles on my DS and get it so that the angle on the output shaft of the TC meeting with the DS is the same as the angle where the DS meets the rear differential. I already gathered that much from this thread, lol. I tried using an angle finder we had here at work, but I couldnt get in right to get it measured. Maybe what I'll try to do tonight is take apart a coat hanger or something and get under the XJ and make one bend to match the TC output, and bend the other to match the pinion, and then measure the angles on it tomorrow at work, then do my calculations from what I get from that. The guys from JackIt also told me to get shims to make the pinion point 1 to 2* lower than it needs to be in the rear so that during acceleration it will be at the correct angle.
 
Ray H said:
Those 2.5 degree shims youve shown are aluminum and dont require removal of the centerbolts.
They dont go under the center bolt, They fit around the head of the center bolt. See how big the hole is?
Click to expand...

Yeah I was kind of thinking that. I just want to make sure I get this put together properly so my center bolt doesn't decide to come unexpectedly out of the axle plate, haha.
 
I'm going to just order the Pro-Comp 2.5* aluminum shims from Summit right now. I'll have them here in 2 days. I'll try them once and see how they affect it, then I'll get some steel ones and put in a new center bolt. They're only $20 shipping and all, and it'll save me aggrivation at the moment. I'm going on an out of town trip this weekend, and I'd like to try to get rid of my vibration before then if I can, so I'm going to give these a shot.
 
Just put the angle finder on the valve cover(thats your T-case angle).Then go to the flat spot(with the hole in the center)on the back of the diff(thats your pinion angle).
 
RCP Phx said:
Just put the angle finder on the valve cover(thats your T-case angle).Then go to the flat spot(with the hole in the center)on the back of the diff(thats your pinion angle).
Click to expand...

You're talking on my valve cover as in under the hood on the top of the block valve cover? And the rear cover of the rear diff? I have a magnetic base angle finder in my hands right now. Is this correct? I'll measure quickly before I leave work. It won't hurt anything to put a magnet on the valve cover or diff cover will it?

I'm pretty much a newbie when it comes to anything along the lines of this, but I'm trying my hardest to learn, sorry if I seem dumb about some things here, we all gotta learn somehow :).
 
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razor2006 said:
I'm going to just order the Pro-Comp 2.5* aluminum shims from Summit right now. I'll have them here in 2 days. I'll try them once and see how they affect it, then I'll get some steel ones and put in a new center bolt. They're only $20 shipping and all, and it'll save me aggrivation at the moment. I'm going on an out of town trip this weekend, and I'd like to try to get rid of my vibration before then if I can, so I'm going to give these a shot.
Click to expand...

Make sure you tighten your ubolts to the correct torque, drive it a few miles and recheck the torque before you take your trip.
 
Yes to the engine valve cover.Not on the diff cover(the 2 holes just on the sides of the cover(see Pic).
100_0954.jpg
 
Okay, here's what the magnet base angle finder I have here at work tells me. With the magnet stuck on the flat spot with the hole on the side of the diff cover (I checked both sides they read the same), starting point would be 90* from this direction, I get 81*. With the magnet stuck on the top of the valve cover, starting point from this direction would be 0*, it reads 6*.

So in association if the needle were to start at 90* on both points I would get 81* beside the diff, and 94* on the valve cover, or if it were to start at 0* on both I would get 6* on the valve cover, and 11* beside the diff.

That would make me at a 5* difference. How do I figure this out from here? Does this mean I would need a 5* shim?
 
no,you cut it in 1/2 which gives you the 2,5 degrees you need. neat trick with the angle finder on the valve cover. If I ever new it I'd long since forgotten it.I'm an old fart but your'e never too old to learn. And shame on me for not mentioning retorquing the u bolts
 
It sounds like your T-case is 6* down(normal is 4-6*)and you pinion is 9*up(that sounds odd).Do you have lift shackles?
 
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Ok, so I spent $30 and got new u-joints 'cause if I have to pull them to inspect I might as well put new ones in. As rusty as the old ones were I couldn't find anything wrong with them so I wasn't too hopeful that the new ones would help. The vibes are still there but seem to be less bad, so I guess they helped some.

I rechecked the driveline angles using the rear flat (thanks for the tip) and here's what I got:

tcase: 6*
driveshaft: 17*
rear: 6.5*

So it looks like my pinion angle is pointing 0.5* the wrong way at rest. I figure a 2.5* shim will be perfect. Does this sound right? I couldn't find one locally so I guess I'll have to order one.

So what do y'all think of the tcase to driveshaft angle? I remember reading somewhere that the cherokee was made to operate at no more than 8* and running any more than that will eventually break the transfer case. Is this true?
 
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