bkeese

I can't find a posting de-coding a 1970 Cutlass rear. I believe it too be a 3.91 posi, is this correct?

2blu442

My favorite reference for things like this is Supercarsunlimited book called "by the numbers". It doesn't show a type O TS code either, but does have a T3 in 1969 which is a 3.91 anti-spin. Is the second digit real clear or could it be a 3 instead of an S?

John

tru-blue 442

On the pass. side, between the pumpkin
and shock bracket, there will be the code.
It may be a bit faded. You can use some emory
cloth or a wire brush, but it will be there.
A lot of times the stamping were very light.
The code could also be upside down and also
facing towards the front of the car.
Most I have seen are facing the back of the car
and upside down. Good luck with it.

My442

1970 3.91 codes:

TO - 12 bolt, W30, W31

SJ - 12 bolt, Cutlass, 442

SZ - 12 bolt, W30, W31 with W27 (aluminum center section)

1970-W30

Factory manual shows no such code for 1970 model year A body. "SJ" is 3.91 ratio, "SH" is 3.42.
"TO" is 3.91 for a W-30, W-31. "TM" is 3.42 for a W-30,W-31.

507OLDS

Can you post a picture of it?

wmachine

The Assembly Manual has all of the codes and way much more! All available free of charge at Wild About Cars

http://wildaboutcarsonline.com/cgi-b...aldisplayed=50

Wild About Cars. http://wildaboutcars.com. An information supersource, especially Oldsmobile. More Olds content than anywhere else on the internet and continuing to grow.
You'll find Chassis Service Manuals, Product Information Manuals (AKA Assembly Manuals), Inspector's Manuals, and other documents that will contain this and much much more.
Dealer Brochures, magazine ads and articles, and the Automotive History Preservation Society library growing daily.
Free to join, free to learn.

69HO43

Check again to make sure it's not an upside down SL. That's a 3.91 but it's from 1969.

RALLYE KID

i tried many times to get on that site to check the rear end codes out and other things but for some reason won't let me on there.

wmachine

All you have to do is ask. Email me and we'll get you going there. Kurt.Shubert@wildaboutcars.com