Have a chance to buy a 67 chevelle posi to put into my 65 cut but was wondering if it would fit. I just want to put the posi in not the entire rear end! Both are 10 bolt.

 

It will physically fit- Control arms and such will all match up- however its likely that you may need a conversion U-joint (two different sizes on the same joint) for your driveshaft to attach to the pinion yolk on the other diff

Should be no big deal though, you can get those at napa

 

RAMBOW thanks for the super quick reply. I don't want to change the entire rear end just the posi "GUTS", really don't even want to change the gears just put the posi in if thats possible.
Thanks. Gary

 

Even if they were the same housing I would just swap the entire unit because if you don't know how to set up a rear end you have no business doing it.
Swapping the housing is MUCH easier and can net fewer problems.

 

Listen to Randy. If you have to change carriers it will have to be set up just like you are changing gears.

 

didn't realize you were just talking about the guts...

yeah i wouldn't try that. Just swap the housings.

 

If they are both stock rearends you cannot change the guts. Chevy 10 and 12 bolts are different than Olds 10 and 12 bolts. The whole rearend should swap though. I believe all of the 64-67 A-body rearends use the same mounts. 68-72 have the same lower mounts, but the uppers are different. If you use adjustable upper arms, you can also bolt them in. I would just swap the whole rearend.

 

Also, the chevys are c clip, and the olds are bolt in.

 

While the two carriers in question will not swap, the C-clip vs. bolt-in difference is not the issue. In fact, in the 1971-up 8.5" axles, the C-clip style carriers can be used in the Olds bolt-in housings with no problems. So long as the axle is retained at the outboard bearing, the lack of a C-clip is not an issue.

 

You would be better off changing the whole rear,but you will need an adapter U-joint if the Chevy rear has the 1310 yoke on it. The widths & mounting points are all the same.The Chevy 8.2" 10-bolt has 28-spline axles,with a 25-spline pinion,& c-clips.The BOP 8.2" 10-bolts have 28-spline bolt-in axles,with a 27-spline pinion.
I "have" put the Chevy 8.2" guts(posi AND gears) into a BOP 8.2" housing.It will work,& there is an old article in an early 90's Hot Rod or Car Craft that mentions this.The pinion seal is the key to making it work.You need the correct one,& there are a few different ones.

 

OK thanks for info! How about a 66 Pontiac GTO 10 bolt into the cutlass? Any problems here? I'm trying to go from a peg leg to a posi and just checking the opitions.
Thanks Gary

 

What gears do you have right now? You could get a locker insert and put it in your current rear.

I see those used from time to time for around $200. They go for ~$400 new

 

The chevy posi 3.08-4.56 carrier is the same as a Buick Olds and Pontiac ratio 3.36 -4.33 carrier (early 1964-1970) 10 bolt 8.2

As stated they are both 28 spline one is c-clip (Chevy) and one is bolt in (BOP)
BUT the spline angle on these axles is different making the fitment of the BOP bolt in (60 degree) spline angle loose rocking fit into a chevy( 45 degree) axle spline side gear in the posi or open diff.

FOR street application you can use the 10 bolt 8.2 posi in the bop housing if needed. Just remember that the chevy 3.08 -4.56 carrier can only be used with BOP gears from 3.36 3.55 3.90 4.33 and up.

8.2 Chevy gears in a BOP housing: Yes this can be done also...BUT there is NO conversion Pinion seal to make the chevy yoke work stock. We have a sleeve made that presses onto the chevy yoke and it uses the 2043 stock Pontiac pinion seal. We sell it for 45.00 if you need it.

Hope summer is treating you all well...Keep cruising, drag racing or what ever you do with your cars!!!

Jim 330 659 7117

 

In addition to what Jim stated about the swap,the BOP rears came with a few different seals throughout the years,so the Chevy to BOP swap might not work,depending on what seal you will need.The housing I used was a 72 lemans 8.2" "P" type rear,with the converging ribs.I installed the Chevy 8.2" posi,with chevy 8.2" 3:73's,& the Chevy yoke.I took the dimensions of the seal diameter in the housing,& the surface on the yoke,& researched it at Timken,& came up with a 6-digit seal.Part #473440.I think it was $12.00.It worked great,& the car has been driving great this year.As far as the spline pitches,yes,they are different,and again,you may or may not have options.If I remember correctly,I used a pair of 71-72 8.5" 10-bolt 28-spline axle shafts in that rear,to jive with the spline pitch,for a better engagement.I did it back in december,but I did take note of every piece,& gave it to the owner,so he knew exactly what he had for a parts reference.I have a copy somewhere in my papers.more of a hassle than what it was worth,but it was what he had with the car,& wanted to know if I could make it all work.I did.I do know that the 2 seals that were mentioned in the magazine article were NOT correct for what I had,but maybe for some of the other housings.