I tried looking for the stamp on the rear and I can't find it at all. The Haynes manual side the front right axle but I couldn't see it.

Is there a way to know what rear you have with the VIN number?

The car is a stock 90 Camaro RS.

 

place car in neutral on jackstands/lift etc

Put a pice of tape on the tire, recording/remembering exactly where the tape orginally was.

Spin driveshaft with hands. Count the number of times the driveshaft rotates until the tire has made 1 complete revolution based on the tape you placed.

The driveshaft will spin x.xx amount of times...

for example, if it spins 3 and 1/4 times, you have 3.23's. A little less than 3 and 1/2 times, probably 3.42's...etc etc

get it?

 

If it is the stock rear, with a T5 it is a 3.42, with a 700R4 it is a 3.23 (was typo'd at 3.32, which is incorrect). Most likely an open (non-posi). Can also check the RPO codes on the glove box lid under the hatch. There is a list of them here on TGO.

If your '90 is truely stock then it has a 3.1l engine, not the 2.8l.

RBob.

 

yea its a 700r4.

I'm asking this because I want to change the fluid and I need to know how much (if any) fluid has to be added for the limited slip (think thats what its called). There is nothing in the Haynes Manual that I saw telling you how much to add.

 

Ahh, for fluid the rear takes about 1.8 qt's. Basically you buy 2 qt's and the additive. Add the additive first then fill with gear lube until it trickles (pours!) out the fill hole.

RBob.

 

Did you or someone else swap in a 2.8?

 

Yea I swapped the engine n tranny from my 89 rs to the 90.

by stock i meant its a stock rear. Sorry bout the confusion.

Since I've never done this before can you tell me what the good fluids to use would be