Gear Patterns and Pinion Shimmingm, Help

[badazz81z28]

I'm helping a friend set up his rearend on a 1978 Camaro. We are using the Yukon Instructions located here: http://www.pirate4x4.com/tech/billav...structions.pdf



The problem is, reading the pattern and comparing it too the pictures is a little tougher than we thought. There is one thing we can see is the obvious development of a "half moon" on the coast side which indicates a pinion too deep. We can also see for sure its not too shallow by comparing the pictures to the install sheet. As we gradually go down, you can see the half moon start to turn into a oval like shape, but not so obvious like the picture. It doesnt change a whole lot on the coast side, but the drive side does slightly from face to flank. What should we do? Go as deep as possible until its too deep? Right now since the .043" started to become an half moon on the coat side, we went down to about .040" and the oval is back. Or is there a range that will be good?

[badazz81z28]

[FlyDoc]

The contact pattern is also not in the center of the ring gear, it looks like the ring gear needs to be moved away from the piñon.
What does the contact pattern look like on the piñon?
How much back lash is there?
Just remember that the TV show tape for 1-2hr for the 30sec clip for setting up a rear end.
Here are the things that must all Aline to get it right.
Ring gear - left/right
Piñon - depth
Piñon - drag (how much effort it takes to turn the piñon)
Hope this helps, good luck, take your time and as many breaks as you need, just remember that the BFH is one tool that is not used!

[badazz81z28]

Yea, I was concerned about the centered portion of the pattern, but the instructions say not to focus on it. The main concern was to be the face to the flank center. I just don't see what I'm really looking for and since this one isnt mine, I dont want to eff it up.

Back lash is at .010"

[badazz81z28]

We decided to wrap it up and call it good! Man it took both of us to crush the sleeve. Big thanks to Big Gear Head (Freddie) for taking a look at the shots for advice. Saved a boat load of $$ by not using the base Hobby Shop!