Was the O-Type 12 bolt cover differential available for the 1966 Cutlass/442?
Thanks
Wayne

 

Not to my knowledge, both the 10 bolt Pontiac style and the 12 bolt cover Olds rears were used in the 67 's

 

The o-type was a late model year addition, available starting May of 1966
Joe posted about this awhile back

 

Well, it's a replacement then as my cars build date is 01-A 66. Previous owner has passed away so I'll never know. Is there a source that details any more information on the differentials. It is I believe a limited slip 3.23. Thats all I know.
Thanks
Wayne

 

The 66 only 12 bolt O type has the flat spring mounts where the 67 and later use the raised mounts.

 

Will this help in deterring which on this is.
Thanks
Wayne

 

That looks like a 67 up mount. Does the spring use a plate with a bolt/nut to secure it or does it just sit there? Can't see enough of the mount to make sure. It also looks like it has a rubber insulator on it,it it does,that's wrong,it goes on top.

 

I'll try to get a better look and picture.
Thanks
Wayne

 

Mike, thanks for all of the help. Much appreciated.
Wayne