Under the Tech Data I could not find a list of gears/rear ends for our cars (82-92) Did I miss it somewhere? I have an 88 SC and I believe the stock specs are: 10 Bolt, 28 Spindle, 2.73, non-posi. Could anyone confirm that?...If there is not a sticky or chart for that info, then maybe someone could list those details for every year.

 

That is not correct.

If the car still has its original rear, it has 26 splines, not 28.

Gear ratio doesn't go with sticker content. In other words, telling us that it has SC stuck here and there on it, doesn't correspond to a specific gear.

Gear ratio, in the "standard" configurations, goes with the drivetrain options. If your SC has a 305 TBI and auto trans, it would have come with 2.73. If it came with a 5-speed, it would have had 3.08.

If it came with a 6-cylinder, it would have higher ratios than that; 3.23 and 3.42 are often found in those cars. However I have no clue whatsoever about the details of the 6-cyl cars.

Gear ratios are pretty much similar between the same drivetrain combos in the Camaros and the Birds.

 

88 was the first year for 28 spline axles was it not?


As for gear ratios, it could have anything in there. You can look up the RPO code to see what the car rolled off the factory with 20 years ago but the only way to know for sure is to pull the cover and count teeth. Its probably got 10 year old oil in there so it wouldnt be a bad idea to pull the cover anyways!

 

According to Dave Shelby's performance book

"...One of the first (differentials) was the 10-Bolt, Saginaw rear which uses a 7.50-inch ring rear. This rear was updated in 1985 to handle more horsepower by using a slightly larger 7.625 ring gear and 26-spline axel shafts...1990 10-Bolt rear ends were upgraded to 28-spline axels..."

So it looks like I have a 26 Spline Axel Shaft