Pzark

I have the rear suspension and axle stripped out of my 1979 L82 four speed. I have no idea what the previous owner did but when I bought the car some 25 years ago it was very obvious that their fingers had been in a lot of places and not in a good way. Anyhow getting back to my question, my hope is to fit a 5 speed in about a year and to get the gearing correct to bring my highway revs down to about 2000 at 60mph I need to determine the back axle ratio so how do I do that. Thanks
Pete

Gordonm

Turn the axle exactly 1 revolution while counting the number of times the pinion rotates. If it goes 3 1/2 times you have a 3.55 if it goes 3 3/4 times you have a 3.70. 3 times a 3.08 and so on.

Pzark

Thanks that is easy enough to do. I appreciate you sharing.

Pzark

Okay it is a 3.7 is that typical for a 1979 L82 4 speed. If so it is probably the original axle. Can anybody enlighten me on that question, again thank you

Gordonm

Yes it is. You can also look at the numbers on the bottom flange of the housing and see the code on the housing. This will tell if it is original. It should be OJ stamped into the housing.

Bills17n72

yep that sounds right ,I had a 79 with a four speed and it was the same as you have ,thou I had the L-48 in mine!

Pzark

I may as well change the oil while the unit is out, what is the best oil that vette guys would recommend for these. The axle feels pretty good no slop or clunking. Thanks again.

TimAT

Also check how much end play you have in the stub axles.
As far as oil-- 2 bottles of GM 88863089 75W-90, and one bottle of GM's limited slip lube.