65tripleblack

Nice, but...........

4 Speed Dave

Questions: 1. What is the electrical cord for?
2. What does the coast side look like?

65tripleblack

1. Used that to drag the pinion instead of the "belt" used by somebody in Connect-i-cut.

2. Therein lies the "rub".

rene-paul

New or used gears? What is the backlash? Looks like to much toe contact, IMHO.
Brgds,
Rene

Critter1

The drive side in your 1st picture doesn't look too bad but the coast side in your last picture doesn't look good. Pinion depth??

Somewhere I have a great drawing of the preferred pattern and the corrections required to correct it depending on the pattern results.

If I can find it, I'll scan and post.

zim64

gear pattern pics...

wmf62

I'm confused... the picture shows different contact patterns but doesn't show an ideal or how to correct from each pattern; just pinion too close or pinion too far...
Bill

DansYellow66

If a new gear set is being used - whose gear set did you go with?

I'm fighting a noise issue in a newly rebuilt 8-3/4 Mopar with Rickmond gears. Pattern looked perfect - still makes noise - removed again and pattern still looked perfect. We are going to replace the gears again but wondering who is left that makes decent gears anymore?

4 Speed Dave

For Corvette rears US Gears are good just call Tom's. I use Motive Pro gears in my Nova and they always set up nice and have yet to have a failure. I changed the front and rear ends to 4.11s on my 1970 K10 truck, Dana 44 front 12 Bolt truck rear with Motive street gears and they also set up nice and are quite. I have just under 4000 miles on the new truck gears and they are as quiet as they were when I put them in.

On Ford 9" also recently used two sets of Richmond recently one street gear one pro gear and they set up fine no noise according to my friend.

The hardest gear set I found to set up was a special 9310 heat treated and REM polished gear set (looked like chrome) from Tex Racing for a prostreet Camaro. This guy would drive the 850 hp stick shift Camaro 90 miles to the track run 9.80's and drive 90 miles back. The surface was so smooth the gear marking paste just smeared all over the place. No noise or anything. He ended up switching to another ration and when the gear came out it looked new. There is something to that REM polishing.

65tripleblack

Thanks Mike. I have those pictures in the Shop Manual.

I believe it was put together this way last time (10 years, 13,000 miles ago) when I had someone do it for me. The shiny area on the coast side of the teeth sure looks like it was meshing exactly the same way before this rebuild. I replaced the posi case and both bearings. Used the same ring and pinion and did not touch the pinion in this rebuild, so pinion depth should be same as it was before.

It never whined on the coast before..........well...............then again the exhaust is so loud and my hearing is so bad that I wouldn't hear it anyway.

Here is a helpful video:

65tripleblack

Re-used ring and pinion. Never touched pinion in this rebuild to replace a cracked posi case and both stub axles. There IS slight runout in the ring gear. It is .004" which is about .002 too much. I'll live with it.

Backlash is between .009 and .013. About .005 too wide but if I close it then the pattern on the drive side moves closer to the toe. It is already slightly closer to the toe than to the heel. It doesn't seem to make sense, because id need to increase lash to get the drive pattern perfect.

The good news is: I'm sure that the coast side is not nearly as important as the drive side, which I like. Very close to dead center heel to toe, and ever so slightly closer to the flank than the face which means deeper mesh for more strength.

65tripleblack

Lash moves BOTH drive and coast patterns back and forth between heel and toe.

Pinion depth moves patterns in opposite directions on coast and drive sides, while also moving them up/down between the flank (bottom) and the face (top).

65tripleblack

I'm no expert here but did you check the pattern all the way around the ring gear. Possible runout causing uneven pattern?

That's the great thing about sidepipes. You don't hear any noises.

DansYellow66

Yes, we removed it and inspected the pattern after about 100 miles - looked terrific, but sounded bad. Even sitting and running on jack stands it sounded like a distant cement mixer listening with a piece of heater hose - all new bearings too. I have been considering switching to louder mufflers.

rene-paul

MHO, again, I was taught that used gears are pattern checked/set up on the coast side. I set my 63 open diff that way. Drive side is checked also but referenced. You are fighting a run-out that is affecting both backlash and pattern. IMO the only way to fine tune it would be to change the pinion shim and "tinker" with it which is a time/parts eater. I tend to agree with 65trippleblack about a full pattern check. If you run it as is, set the case bearing pre-load to .010/.005 each side, then re-check pattern/run-out. Keep us informed.
PS, Did you check the pinion bearing rotational torque with the case removed?
Brgds,
Rene

65tripleblack

How much did you preload the side bearings. No more than 0.010" I hope. Are the races brinnelled from too much pressure?

DansYellow66

It was set up by a local mechanic who rebuilds most Mopar and GM rear ends for the hot rod and restoration community here so I don't know. Mostly just fishing for references for better ring and pinion gear producers.

65tripleblack

Thanks again to all who helped, with a special thanks to 4 Speed Dave.
No clutch banging or grabbing. Smooth operation, even before "figure-eight" operation. Gears are quiet both on the pull and on the coast, and, of course:

4 Speed Dave

Glad to have helped you with the posi shims. Now those pictures are what I'm talking about!!!