I have a 10 bolt rearend and what are the factors that make a posi or is it just a limited slip. The #'s are 1129 9799700 I had the back off,but don't know what to look for. Plus what happens if you turn one of the axles?
Hmmm, little bit tough to explain but if you have the cover off, look for springs between the gears. You look through the opening in the center section of the differential.
If that does not explain it well enough I can see if I can find a picture of what to look for.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
for what it's worth, I had the diff casting number written down from a friends 70 GTO 400 4 speed rag. I wrote down 9799100, but the 1 might be a 7 as in your 9799700. The casting number will not tell you if it's posi, you've done the right thing by looking for the springs.