McGeeXJ

I just finished installing my new lift. First time I've ever done anything like this. It's a rustys 4.5 with full springs. I have a 1999 cherokee sport. I just took it for its first drive and it's scaring the **** out of me. I get some real bad vibes from 25-35 mph, and sometimes when I let off the throttle to slow down, I get a real nasty sound like I'm dragging my driveshaft along the road. It sounds like something is scraping or something. My kit came with a transfer case drop and 6 degree shims. My next purchase will be an sye kit, but I need to make this car drivable until then, I'm scared to drive it incase ill be doing more damage.

Tomorrow I'm taking the jeep to get a 4 wheel alignment, new tires, and rims put on. I doubt the alignment will help my noises.

I'm a real big noob with this stuff and I'm learning new things everyday, so please don't assume I know something, I just might, but don't give me the benefit of the doubt.

Please help, thank you.

Slugger

you'll need a slip yoke eliminator and shims to adjust the rear driveshaft angle.

McGeeXJ

I know this, I'm getting one, and I shouldn't need the shims once I have one. My problem is I don't have the money to get one right now. The shims and t case drop i have shouldn't be giving me vibes this bad. I need to fix this problem first.

RubberSideUp

Without the SYE and CV/double cardan shaft, you're going to have to try and get the transfer case output shaft parallel with the axle yoke. This could required removal of the transfer case drop and/or the shims. Depends on how much the axle rotated (shackle angle, etc). Use an angle finder and measure then determine your course of action.

ohio95xj

You should not have vibes like that at 4.5 with a t case drop and shims. It seems like there is another problem.

McGeeXJ

Please elaborate further, especially dealing with the shackle angle etc part. I just assumed that rustys t case drop and angle shims would put my driveline where it needed to be. I really need some help. I could've made a huge mistake with my install. The instructions weren't as thorough as I hoped they would be.

I had to loosen the shackle and angle it as forward as it would go to install the leaf spring. Once I got the bolt in, I had to pull it straight back until it was almost perpendicular with the ground in order to install the nut. My lift instructions said to torque the rear shackle leaf spring bolt to 25 pounds, I torqued the shackle frame bolt to the same spec. I did this lift by myself, with no real experienced advice. I'm not very auto savy, although I am getting there.

Everything I installed is torqued to all specs noted in the instruction, and weren't torqued until the jeep was on axle stands so that the weight of the vehicle was on the suspension, like I was instructed to.

I am lost when it comes to adjusting these angles and what not, I just don't know what to look for.

TheCK4x4

The shackle angle shouldn't cause vibes, and I was at 4.5 with a 1" t case drop and no vibes or anything, also what do you mean a 4 wheel alignment? Are all of your u joints good? Do they have play?

mr white

You need to make the pinion angle parallel to the transfercase output shaft. I'm assuming the shims made it so your pinion was pointed at the shaft. This is wrong since you do not have the SYE and double cardan driveshaft.

McGeeXJ

I thought all alignments were 4 wheel. I'm going to check my joints tomorrow morning, after reading a few other threads I'm thinking this might be the problem.

McGeeXJ

Yes you are right. The large end of the shim is in the back to point the axle up a little bit towards the t case. This would make them not parallel. I'm not understanding this fully though. Are you saying I only need the shims if I have an sye?

This is some real helpful info guys, I really appreciate it.

dogger15

oh my....

McGeeXJ

I'm a noob asking for sincere help. All I want to do is learn. It's just me, a Haynes repair manual, and the Internet. Well... And autozone I guess, but they can be a bunch of dicks depending on the mood they're in.

Cut me some slack.

mr white

Make the pinion parallel with the output shaft of the tcase.

McGeeXJ

After researching for awhile I've decided to remove my shims and go from there. I'll then purchase an angle finder and see where I'm at.

mr white

Its not terribly difficult to eyeball.