507OLDS

I have a few set of gearsets & rebuilt Eaton posi units,for 12-bolt Chevy.The posi units are rebuilt with the good clutches,not the junk that comes in the new ones.

GM 3:31,dated 1966,with 3-series Eaton posi,$450.00
GM 3:55,dated 1970,with 3-series Eaton posi,$450.00
Richmond 3:73's,new,for 4-series carrier,with 4-series Eaton posi,$500.00

Olds462

Do you have any posi units for a 1970 'O' type 12 bolt?

507OLDS

I have the #588 posi unit,for the GM 3:42-up gears,for 28-spline axles,and I also have the #672 posi carrier,for the same GM 3:42-up gears,for 31-spline axles.
The #588 is $450.00
The #672 is $500.00
Both are rebuilt,and have new bearings installed.
You can run the new Richmond 3:42/3:90 gears with these carriers,if you mill .100" off the backside of the ring gear.I've done it many times with no issues.

Olds462

How would I go about finding out what spline shafts are in mine?

507OLDS

The 31-spline rears were only offered in late-67 & 68.All of the other O-axle rears have 28-spline axles.If your rear is not original to the car,and are unsure of the year,you can remove one of the shafts & count the splines.There are 4 nuts holding it in,located behind the brakes.You do NOT need to remove the rear cover to remove the axle.

Olds462

I will check to be sure and get ahold of you. Thanks for the help.

Olds462

Hi Brian, Sorry it took so long to get back to you. Work is crazy lately. I counted the splines on the shaft and it's a 28 spline shaft. Do you still have a posi available for this. Looking to go with a 3.42 gears for this. If you could please send me a PM.

507OLDS

Yes,I still have the posi unit.