jwe2

Just installed a RC 4.5" lift last weekend as well as an Iron Rock off road sye kit. The kit is simply the seal flange, fixed yoke and refurbed front drive shaft for the rear. I am having trouble figuring out how to measure the drive shaft and rear pinion angle to figure out what size shims to use. I am making the shims myself in a machine shop, so I would rather make the correct measurements to avoid wasting time making multiple size shims.

I bought a cheap-o angle finder and measured the driveshaft angle and the pinion angle and it seems there is about a 10 degree difference. Is that the size shim I need? From what I've read that seems like a lot. I'm not sure if I'm measuring correctly or if there is some simple equation I need to use.

I can get some pictures of the pinion and drive shaft angles if it helps.

On that note, The front driveshaft/pinion also seem to be way off. I know this is adjusted by caster, but there doesn't seem to be a lot of room to adjust back. This seems strange because the kit came with fixed LCA's so I assume they should work......

Thanks

freegdr

this is what your aiming for

jwe2

Thanks for the pictures. yea, the rear pinion needs to be aimed at the output shaft. I know that I need as close to 0 degrees difference, maybe 1 or 2 degrees less to account for axle wrap during acceleration, but I'm having trouble figuring out how to get there without lots of trial and error, (and wasting steel).

Modestmike

Don't they sell shims? Something like 3 or 6 degrees? Someone correct me if I'm wrong.

freegdr

http://rustysoffroad.com/mm5/merchan...y_Code=LEAFACCyes they do

freegdr

how far off is it pic ava?

jwe2

yea I'll go take some pics real quick with the angle finder on there.

freegdr

try and get them just like the posted ones tc to rear axle

jwe2

let me go grab one more of the whole thing like you said.

freegdr

are you having vibration probs, and has the lift settled yet .how long since you installed the angle will decrease when this happens

jwe2

jwe2

The vibrations are awful. at 15mph and higher it feels like sitting on an unbalanced washing machine. I just installed the lift this past weekend so it hasn't had much time to settle. I'm afraid to drive it much with these vibs so I don't think I'll be able to get it to settle much before addressing the problem.

freegdr

you said the front is bad you sure thats not the prob ,the rear dont look to bad you could always drop the tc crossmember with longer bolts and washers .what year is this

Xjay98

Sometimes if you're angle is way off you also change the position of the lower shock mounts. Ask me how i know. Expensive mistake. Anyway try to be 2*-3* from each other. My d-shaft is at 15* and the diff at 12*. I measured the diff angle on the flat part of the diff case. Dunno if it matters. No vibes up to 90mph. Looks like you need to add 6* or drop the Tcase. Heres some reading material.. Read the the ones on the left.

http://www.4x4wire.com/tech/pinionangle/

For the front check your caster angle. You can also tell by looking at your springs. Not precise but heck. It will be bowed.

Xjay98

Forgot... As the car sits look at how your spring bucket is sitting.