My ‘71 Convertible has the THM 400 Automatic and Limited Slip differential. What was the standard axle ratio for this car? And what were the optional ratios? OR where may I find this information?

Thanks!

 

Refer to the 1971 Info Kit from GM pg: 170 and pg: 182 (From the GM Heritage Archive)

 

Also available by searching the forum. Here's an old thread with the same information:

https://classicoldsmobile.com/forums...-ratio-110849/

 

 

Thanks, all - I tried the search bar and got nothin’ - user error no doubt.

 

Maybe not - I found that with a Google search using “site: classicoldsmobile.com ratios”.

 

Considering you won't know if you have the STD ratio or an optional ratio just asking blindly like there is only one answer is not the way to do it.. Get off the couch and get under your car with a jack and put in neutral and since its a Anti-Spin as you say simply count the yoke turns to one wheel revolution . I like to use the valve stem as a pointer down to start and count yoke as it turns 180 degrees at a time so say 2.5 turns well 2.56 .... 3-1/4 turns well 3.23 , etc not brain surgery and see if ya can find the code stamp on the right side axle tube while your there and maybe it matches what you find