Setting up gears. Please check the pattern (image)

[Blazer79]

Hello:

I'm helping a friend setup his gears on his 10 bolt rear axle. It's a pontiac firebird 1979. Can you believe he had 2.43 gears!!!? /forums/images/graemlins/shocked.gif The pinion was almost larger than the ring.

We're installing a set of used 3.73 gears I bought from Mudzer a long time ago but that I never installed because I got a couple of 14 bolt / Dana 60 axles for $500.

Attached is a drawing of what we were able to achieve reusing the shims on the old gears.

According to a manual on Randy's R&P, when setting used gears, we should care more on the coast side than the drive side. We feel that the coast side is better than the drive side. If we try to improve the drive side, we're sure we'll ruin the coast side.

Please give us your comments. Thanks!

 

[azblazor]

That pattern looks pretty good to me - but I am not experienced, I'd give a lot of weight to the instructions from Randy's. I'll give you a bump to the top.

 

[HarryH3]

I would pull the drive side mesh point back closer to the center of the teeth. The coast side doesn't see nearly the amount of torque that the drive side sees, so I prefer to setup the drive side perfect. /forums/images/graemlins/cool.gif I think you need to take some shims out of the pinion to move it towards the front of the car. Setting the pinion depth is easily the most aggravating part of setting up a gearset. Lots of trial and error is involved if you don't have an (expensive) pinion depth tool.

 

[Mudzer]

That pattern looks fine. Did you check your pinion bearing pre-load with inch pound torque wrench? Make sure you get this set and be sure to loctite the pinion nut. Since you have checked pattern and determined the pattern looks good you need to check backlash. This is done by mounting a dial indicator to a flat surface such as the pan mounting surface using a magnetic base. Set the Dial Indicator anywhere on a tooth of the ring gear and grab the pinion yoke firmly. Now rock the ring gear forward and backward easily (without moving the pinion) to check back lash. Check the backlash on an area of the gears without lube or gear pattern paint. Set the pattern within spec. or you will have problems. I broke a ring gear once because of too much backlash.

Looks like you are on your way to being a gear setup pro! /forums/images/graemlins/grin.gif

 

[HarryH3]

Did you look closely at which side is drive and which side is coast? Every picture I've ever seen of a correct pattern showed the drive side nearly centered on the tooth. The pic above shows the drive side contact to be too close to the toe of the gear. The coast side looks pretty good, but the drive side doesn't.