77 rear differential

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Jan 16, 2009 | 06:25 PM

KevinZ

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From: Newfane NY

77 rear differential

Here is what I found when I went to pick up my rear diff after new seals were installed:

History:

Cracked rear cover...all seals were leaking..."no noises"

Stub shafts are in great shape, no end wear or excessive end play.

She has a Torker II manifold and stock carb and automatic transmission.
I was worried about the cover breaking loose and wrecking the entire rear of the car. (Figured I was driving on borrowed time)

I took the unit out and to a "Vet" mechanic expecting the worst, and when I took the cover over to finish the repair, I saw this. I asked him about it and his response was, that won't bother...

(All I can think of was previous owner chiped it durring disassembly because there was no debris or meatal in the fluid....)
The chip is on the access side of the carrier.

I've been driving her for a couple of years, but decided to get the new cover on, new fiberglass TRW spring in and stop the leaks.

Still pondering my next move...

Jan 16, 2009 | 07:35 PM

OMF

Melting Slicks

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From: Salmon Arm, BC

I'd just dress it out, don't leave any burrs on either side of the tooth, bolt the cover on and go have fun. That won't cause any problems

Jan 16, 2009 | 07:40 PM

HT1663WB

Melting Slicks

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From: Clayton New Jersey

I also have a 77 Vette but it has the 4 speed. When I took mine apart, same thing...I have the factory 3.70's. I was also told it wold not hurt anything. That was about 7 years ago. Now she's pushing in the area of 400 hp and no problems.

Bill

Jan 16, 2009 | 07:43 PM

mikep3

Burning Brakes

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From: Baldwinsville, NY

Who is the spring

Do you like the new rear spring?

It looks like it has been snowing 2 to 3"/ hour all day up in Oswego Co.

Jan 16, 2009 | 07:46 PM

GTR1999

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From: Connecticut, USA

Kevin take a dremel and remove all the sharp edges. I personally would replace them but that's me. I'd also work on that posi but then you're getting into a rebuild. Too bad you didn't install the seals yourself, are you sure the chip was there before?

Jan 16, 2009 | 08:24 PM

KevinZ

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From: Newfane NY

Quote:

Originally Posted by HT1663WB

And I thought I'd NEVER hear this... This is one consideration. Glad to hear it is possible...

Quote:

Originally Posted by mikep3

Do you like the new rear spring?

It looks like it has been snowing 2 to 3"/ hour all day up in Oswego Co.

This TRW got the best reviews at the time I purchased it.. Can't wait to get her back together...
Yes, The snow is as bad as they say... and cold... (more in a general post)

Quote:

Originally Posted by GTR1999

I have had mixed emotions to the new gears as I have heard they are noisy...
If I had the tools and the experience I would tackle this, and kick myself for not as 'where did the chip come from' thought crossed my mid as well

Jan 17, 2009 | 08:39 AM

GTR1999

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From: Connecticut, USA

Quote:

Originally Posted by KevinZ

And I thought I'd NEVER hear this... This is one consideration. Glad to hear it is possible...

This TRW got the best reviews at the time I purchased it.. Can't wait to get her back together...
Yes, The snow is as bad as they say... and cold... (more in a general post)

I have had mixed emotions to the new gears as I have heard they are noisy...
If I had the tools and the experience I would tackle this, and kick myself for not as 'where did the chip come from' thought crossed my mid as well

Kevin,
New gears are cut a little different then the original GM,which are long gone now. I use Tom's US gears and have had excellant setup with them. The other choices are Yukon and Richmond. Not sure if Motive is making any? Yes to a degree you'll hear some gear noise with aftermarket but a lot has to do with setup procedures used by the builder. Again I've had good results using Tom's gears.
Dress up your gear and see if it's quiet. You can always remove it and rebuild it.
Good luck

Jul 20, 2009 | 10:32 AM

KevinZ

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From: Newfane NY

Follow-up

Well, we're back on the road.

Thanks for the input, as my choice for rear lube changed. I went with the GM additive and Lucas 80w90. She's a daily driver, plus they were out of the heavier -w140.

Further research and Gary's recommendation I changed to Lucas.
Synthetics have not gotten the best nod, (not that they don't work)and I'm somewhat a traditionalist.

Dressed the 'chip' and re-installed everything. And We're having fun again!!!!

The Beavertail spring is great, but I went with the heavy spring and haven't found longer bolts to bring the ride height to spec. Rear half shafts are angled too much for my liking.

I have the 255 60 15 tires and no problems of clearance!!

Pics to follow!!!