Pinion/Spring perch measurements...am I wrong?

[GI-John]

Alrighty, I've decided on a 8.8 axle after a few failed attempts at a D-44.

I'm trying to get all my measurements together for the correct pinion angle/ perch placement etc... here is what I have:

stock D35 pinion has a +4 degree angle in relation to the spring perch (from my measurements, pad level) I plan to incorporate an additional 4* to compensate for an additional 1.5" lift when the new axle goes in (+8 total from spring perch)

Does this sound wacky? What have you done to compensate for this? I haven't had any issues with vibes at all and would like to keep it that way.

Ideas are welcome...

John

 

[CRASH]

In my experience, it's really hard to try and calculate spring perch angle until everything is under the truck and the weight of the truck is resting on the springs.

Too many variable to try and account for otherwise.

CRASH

 

[LBEXJ]

I'm sure in order to get the perches set to the exact degree angle, Crash is probably right. I've read too many other threads concerning the same subject, and this is the typical response.

Then again, why does it matter if it ends up at exactly the correct angle? You can shim it to dial it in if it's not perfect. Here is a link to a write up where this guy swapped his D35 for and 8.8. http://www.bc4x4.com/tech/2003/xj88/ ...IIRC, he measure the angles on his D35 and set the new perches on his 8.8 at the same angle.

I'm looking to make the same swap except I'm replacing a 27 spline 8.25. I'll more than likely measure the angle I have then weld the perches on the 8.8 to the same angle ... then shim if necessary.

Hell, I can fawk up just as easily as the next guy ...

Les

PS: John ... have you found an 8.8 yet? You going to get one with disc brakes?

 

[Beezil]

hey guy, you are whacko.

its time to sell the jeep.

 

[GI-John]

Definitely going with discs. I'm doing the 96 booster/master this weekend too. I just have to get the time and go pull it. Most want 300 or more.

I'm having a ball searching for info on this swap...the more I dig, the more I like.

I've found that my local JY's dont know shit about axles....and will sell things out from under you in a heartbeat....

And dont like to work weekends....WTF?

Loving (and hating) every minute.

John

 

[GI-John]

hey guy, you are whacko.

its time to sell the jeep.

You're just jealous that Rev has more pics of me than you in his movie. :rattle:

and no, I won't sell the Jeep... :moon:

Just trying to get this right the first time. :read:

 

[Beezil]

You're just jealous that Rev has more pics of me than you in his movie. :rattle:

and no, I won't sell the Jeep... :moon:

Just trying to get this right the first time. :read:

funny thing is, he calls it a movie!

 

[roXJeepr]

Why waste the time and effort calculating when it may or may NOT come out correctly. Just make sure if you do it the way crash said, that you have about the same weight as running weight i.e. don't have an empty fuel tank and don't take out stuff from the back that you normally carry. Also jump up and down on the back to settle the springs back before tacking or welding the perches. It's a pretty good project, so have fun with it!

Dale