Help with reading ring/pinion pattern

[5akman]

New to setting up gears. This is a GM 14 bolt semi float, re-gearing from 4.10 to 4.88's. This is the first try with the new set up in the differential using some "set up" bearings on the pinion with original pinion and ring gear shims. In an attempt to keep from pulling the unit out a dozen times in pursuit of perfection, I thought I'd ask for some advice here based on my pics. 2 pics of the painted ring gear teeth and 2 pics of the painted pinion teeth marking the ring gear.

 

[crazy4offroad]

Looks like too much toe contact. Try to shim the ring gear (carrier) about 0.005 - 0.010 away from the pinion. Might just move a 0.005 shim from one side to the other and recheck. After that if it looks like you don't have enough root contact you may have to add about 0.005 to the pinion. In the pic "gears.jpg" the depth looks good, just too much toe contact on the "power" side of the ring gear teeth.

 

[5akman]

"Crazy", thanks! That will save a ton of time of trial and error on my part. I'll proceed on with your recommendation.

 

[crazy4offroad]

Glad to help. Don't forget to recheck backlash once you get the pattern right.

 

[MikeB]

https://www.google.com/search?q=rin...#imgdii=ZSCU3910nsSzTM:&imgrc=Nk4wepynSq7RPM:

 

[5akman]

https://www.google.com/search?q=rin...#imgdii=ZSCU3910nsSzTM:&imgrc=Nk4wepynSq7RPM:

I'm getting a head ache from looking at all those patterns! I'm working on doing "crazy's" recommendation, hopefully its as easy as move the diff to the left!

 

[MikeB]

I'm getting a head ache from looking at all those patterns! I'm working on doing "crazy's" recommendation, hopefully its as easy as move the diff to the left!

Didn't mean to overwhelm you!

I've only done three R&Ps over the years, all GM 10- and 12-bolts. Seems like I used the diagrams and recommendations from Randy's Ring & Pinion on my first.

Gonna take my current 8.5" 10-bolt from 2.73 to 3.??? sometime soon, and I will have to re-learn a lot. I do remember that it's a lot easier to get a picture perfect pattern with new high quality gears, such as GM or Yukon. A guy I who know who has done literally dozens suggested I concentrate on the "coast" side when working with a used set.

 

[crazy4offroad]

A lot of times you can take the old carrier shims out, keeping them oriented from whichever side they came from, maybe use bread ties to keep them all together for each side, and even use the same amount of pinion shim from your old pinion and come really close to being set up right on the first try. Everything you adjust affects everything else. Mesh pattern, pinion to ring gear depth and backlash are all related. That's why typically you have around 0.005 - 0.012 to play with for backlash, it's just too hard to get it perfect.