bj1k

I have 3.90 gears in my 72 now . They are too low and I want to go back to the stock 3.36's but none of the companies that I checked ( Summit and Jeg's ) sell the 3.36's except in Richmond gears and I have been told that Richmond gears tend to be noisy . Can anyone recommend a company that handles the stock type 3.36's without the noise ?

'75

Zip has them, not sure who made them though.

http://www.zip-corvette.com/catalog/...category/7593/

GregS_72

give Tom's Differentials a call

68/70Vette

Tom's. My 68 and 70 rear ends have all Tom's stuff. Well, OK...the transverse springs are VBP composite springs. I was one of the last customers for which Tom would rebuild the differential, and build up other parts such as the trailing arms. This was right before he left California for Idaho. For my 70. the differential was built up by Mike Dyer (spelling?...tracdog) using Tom's parts.

doorgunner

I did a search last month and found several sites that sold GM differential gears from the 2.90(s) to the 4.XX(s).

The prices varied per set by about $200 between the different vendors.

You can occasionally find unused gear sets on EBay @ 50% discounts.

bj1k

What do you mean by "unused" , NOS ? I've been looking . Haven't seen any. Thanks

GTOguy

Used GM sets, if they are pull-outs, are usually perfect. High quality and cheap. Just not easy to find. Most of these low ratio gear sets were pulled early on so a 'high performance' (low top speed, high winding engine) gear could be put back in. Today, with speed limits higher than 55mph and $4 gas, a 3.08 or 3.36 makes excellent sense. Been running a used 3.36 GM ring and pinion in my '65 GTO since 1990.....and it's quiet as a mouse.

Z06FEVER

Are you interested in selling the 3.90's?

doorgunner

Sorry...I should have said "slightly used".......as GTOGuy stated.

NOS would probably cost as much as a completely rebuilt 3.36 differential.

Dean_Fuller

I have been looking for a lower than 3.08 rear for my 72. Where did you find 2.90 ???

Sorry for the misdirection.

OMF

If your interested, I have a set of 3.36 I just pulled from my car. They are still in the rearend, they have about 77K miles on them and are quiet. I can take a pattern swipe take a pic and send it to you $125 US plus shipping.

GS977

I have a set of 3.08s that came out my 72. original GM gears. and also a set of GM 3.36s I just pulled out and replaced with 3.70s.
$75.00 + shipping for the 3.08 or 3.36s if anyone wants them. they were quiet. never made a sound.

bj1k

Thanks for all of your replies guys. I just found a nice set of used stock GM 3.36's on ebay from the Bobby Watts speed shop .

bj1k

PM Sent

bj1k

Rear section comes out tomorrow. 3.90"s come out Tuesday and the 3.36's go in . Love them highway gears. Maybe have to plan a road trip.

vetteus

I have the original set of 3.36 gears in my 73 and am happy with the gearing but have often wondered what a set of 3.73 gears would be like. I see quite a few sets of 3.36 offered on summit racing...

http://m.summitracing.com/search?keyword=3.36+gears

bj1k

You might be happy with the 3.73's but the 3.90's that are in mine are only good for light street racing. No good for prolonged highway speeds and that is what I use mine for. Summits 3.36 gears are Richmond and the cut is said to make too much noise.

bj1k

I just put the 3.36 rear back in last night and took it for a test ride. What a difference ! It's like getting my 4th. gear back and I no longer have to skip 2nd. gear. ( 2nd was useless ) I'm puzzled why anyone wants to put up with all of that whining . The engine is going 90 mph but the car is only going 40. Talk about wearing out the engine ! There is a high performance engine in my car so that might make a difference but the car seems much quicker now with these gears.

gdh

A friend gave me a 3.36 rear last summer that he had originally planned n dropping in a project. Sold the project and his wife said to clear that thing out of the garage. Thought I'd try it so pulled the 3.70 and swapped in the 3.36. I have to agree that it is a nicer while driving on the hiway.

carretera

Running 4:11s now, need to change.