Is there a way to find out what the #is without taking the cover off. I have an '89 **** brake rear with limited slip diff and wanted to put a torsen diff in it. The torsen has 28 splines and I wanted to be sure if I needed to find replacements before I started taking things apart. Thanks, Rob.

 

Do you have a 9-bolt or a 10-bolt? The torsen only fits the 10-bolts. And the only way to be sure is to count the splines on the axle... 89 was the changeover year, you could have either 26 or 28.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

The rear is a 10 bolt but I don't have the codes off the tube yet. I'll have to try to get it tomorrow when I can get underneath easier. Can anyone decode it after I get the numbers?

 

The code on the axle is 6PMC1002. Can anyone tell from this what axles are inside? Thanks in advance, Rob.

 

Best guess at decoding.

6PM = ratio (my list doesn't list 89 ratios.) Depending on engine and tranny it could be 3.08 (manual) or 2.73 (automatic) if it was a V8 car. 3.42 if it was in a car with a V6.

C = Buffalo assembly plant
1 = Day shift
002 = Day of year. Jan 2

From that I have to assume it's an early 89 diff and would be before they changed to 28 splines. The only real way to tell is to pull the axles.

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Stephen's racing page

87 IROC-Z Pro ET Bracket Race Car and knocking on the SuperPro ET class
383 stroker (carbed) with double hump cast iron heads and pump gas

Best results before the engine blew up
Best ET on a time slip: 11.857
Best corrected ET: 11.163
Best MPH on a time slip: 117.87
Best corrected MPH: 126.10
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!

Member of the Calgary Drag Racing Association