66 posi rear

will the posi case and gears from a 66 Riviera fit into a 67 skylark rear end ,or will the whole thing drum to drum fit under it. John

 

The Riv is a 9 3/8" ring gear. Your year buick is a BOP ( Pontiac) 8.2" ring gear.

 

Nothing will interchange between the two.

 

thanks

---------- Post added at 12:45 PM ---------- Previous post was at 12:35 PM ----------

could anybody offer any insight as to what model buicks or GM's I should look for posi tracs . Thanks, John

 

could anybody offer any insight as to what model buicks or GM's I should look for posi tracs . Thanks, John

 

Hi John. If you mean Junkyard crawling, Look for a Station Wagon. A lot of them have Posi Cases. If it has a Hitch it might have higher gears too.

PONCH

 

My wife bought me a 3 series posi differential from a 66 GTO off of ebay for Christmas and unfortunately I have a Chevy rear under my 66. If you are interested send me a PM.

Scott

 

PM sent

 

Hey ive been looking for a posi for my 68 riv. And that 66 will fit fine . What is the gear ratio and seriously if u want to sell it give me a PM!

 

nO THE POSI WILL NOT FIT IT IS THE ONLY YEAR THAT HAS EQUAL SIZE CARRIER BEARINGS. Have the guy that has the posi tell you if the bearings are the same or different. YOU NEED 2 different bearings.

If his unit does not fit the bill I do have a set of 3.07 and posi unit for the 68.

Also you have to know what ratio you are running and get the correct 2 3 4 series carrier to go with it. Ask all the questions before jumping. Jim

Jim - J D

---------- Post added at 02:44 PM ---------- Previous post was at 02:40 PM ----------

Well in my opinion - BUY NEW... Your money will be MUCH better spent. What ratio do you have in the car? This will let you know what series posi unit you will need.

Car to scavenge for posi - 1964-1972 Pontiac GTO, Lemans, Tempest, 69-72 Grand Prix, 1964-1967 Buick Skylark, GS, Special, 1964-1967 Oldsmobile F85, Cutlass, 442 That is about it.

If you are interested in a NEW posi I have Auburn that will fit 2.93 3.08 3.23 3.36 3.55 3.90 4.33 ratios and Eaton units that will fit 3.36-4.33
I do have a few ORIGINAL GM Posi units we can recondition also 3.36-4.33 ratios they are the SUPER DUTY 4 pinion posi units

Good luck on the hunt. Jim - J D

 

Yes i have a 3.07 one legger. I'm ideally looking for the 3.23 that came in most rivieras ordered with a posi. I'm pretty sure the 3.07 and 3.23 are of the same series. I do know for sure if you get the 3.73 you need a carrier with thinner material ware the ring gear bolts to. Yes a different series carrier.

 

Be sure to check closely though. The '66 Riviera I owned which had a posi was a 3.07.

 

ha ,,, yes for sure i will check if i happen to come across one