Good afternoon, I had to come to the experts before I made this purchase. I wanted to know if this is truly a positive traction chunk and will it fit my 1975 Oldsmobile Delta 88? Also, are there any other options to add positive traction to this rear end? I believe it is a 12 bolt 9.3








I wanted to know if this is truly a positive traction chunk and will it fit my 1975 Oldsmobile Delta 88?

 

That is not a 9.3 it is a 8.875 Pontiac posi unit from 1965 - 1970 era
I REPEAT----- NOT A 9.3 OLDS center!!!!
The cover this posi unit fits has a 10 bolt cover and 12 bolt ring that measures 8.875 and has 31 spline axles AND will only fit the 1965 - 1970 era because it has 30 degree cut axle spline side gears.
Jim
JD race

 

NO OTHER options than you to find a good used unit. Sorry.... Same with gearing. NO AFTERMARKET POSI OR GEARS.... Just bearings for rebuild of what you have.

 

Thank you for the help. Definitely saved me.

 

The ring gear is NO GOOD with out the pinion too. So do not let them think your getting a ring gear worth something - unless the pinion matching goes with it.

 

I have a buddy that has a 76 Olds Custom Cruiser. He used a Corvette posi unit in the big Olds rear axle. He had to use the 3.08 gears with it.