73 Gville Rear end

[sscherin]

A friend has a 73 Grandville with a blown rear (hole in the side parts hangin out kinda blown)

what cars will the rear axle swap from?

I'm gettin that Darkside feelin http://forums.performanceyears.com/groupee_common/emoticons/icon_smile.gif

GURU: One who knows more jargon than you

Scott Schering
70 Firebird 455 12.34 @ 108.2
Http://www.pontiacs.org

[sscherin]

A friend has a 73 Grandville with a blown rear (hole in the side parts hangin out kinda blown)

what cars will the rear axle swap from?

I'm gettin that Darkside feelin http://forums.performanceyears.com/groupee_common/emoticons/icon_smile.gif

GURU: One who knows more jargon than you

Scott Schering
70 Firebird 455 12.34 @ 108.2
Http://www.pontiacs.org

['ol Pinion head]

Scott,
Basically any '71-76 Chevy-Buick-Olds-Pontiac coil spring big car rearend will bolt in. Make that no station wagon rears (leaf spring), no Cadillac rears, no Riveria rears. Best bet is going to be a rear out of '71-76 Pontiac Bonny or 71-74 GV (8 7/8" MP series rear) due to no messing with driveshafts. I usually get a few Bonnys & Grandvilles in a year to pull motors, etc out of...if you were closer, I'd give you a rear out of one of these. Might do some ck'ing close by as these rears usually go straight to the crusher after the boat has been picked...might be able to find one for the trouble of pulling it out...

Further ID'ng the early 70's big car rears...In the '71-76 CBOP big car rears, you will have 3 different styles:

-8.5 corp 10 bolt r/e (in this hsg it has 28 spline c-clip axles)
-8 7/8" MP series 12 bolt (original in Will's GV) bolt in axles with twelve 9/16" headed rig gear bolts...believe round cover.
-9 3/8" Buick...Super tough rear. Has ten 3/4" headed ring gear bolts attaching ring gear & 31 spline bolt-in axles. while mainly used in big Buicks, many of these found their ways into Olds 98's.

Both of the latter styles of rears are tough to find good ratio gears for, as factory built 3.23's & 3.42's very sparingly. Just mention this for those who might read this later & are trying to get their boat to fly http://forums.performanceyears.com/groupee_common/emoticons/icon_wink.gif

Good luck.

[Michael Farich]

If I might add, in '76 at least, for B-body GM, try to get a rear out of a car with larger than a 350 engine. I bought a posi out of a '76 Olds 88 350 engine car and it has a physically smaller looking center section with the vent on the center section instead on the axle tube like the ones that came out of 400 and 455 cars.
I have a '75 Riviera 2.93 posi rear in stock here. Never realized they were different than other B body's. Is it location of the mounts?
By the way, I'm using a rear out of some big old Buick in my '73 B-body Pontiac now. It is super tough - I put a couple hundred thousand miles on it, had different shift kits over the years that hammered the U-Joint rollers into the trusses, broke the CV joint pieces, and now a 455 that hammered rollers into trusses again so I went to Lakewood joints to cure that, but that rear end (knock on wood) has never given me one bit of trouble. It's a 2.56 posi.
That's another thing to keep in mind. By '76, most of those B-body cars had either 2.56 or 2.41 gears (for 400 and 455 engines, respectively). C body '76 buicks had 2.56 even with 455's though. If you want deeper gears, look in '71 cars - they had a little bit deeper gears then. Maybe 2.73, 2.93, 3.08. We had a '71 Cat 350-2bbl car that had 3.23 posi in it. My '73 had 400-2bbl and 2.93 posi originally, but I've seen some of them with 2.56.
Someone once told me that the Olds 98 rear was alot different, and from the above post I can see why. It was suggested that it was unusual enough to be harder to get parts for. If they're easy enough to get, though, and they are really that tough, then why not, I guess.
Mike

[grandville455]

i have a 74 2 dr gv with a 2:93 one legger would love to find a posi for her http://forums.performanceyears.com/groupee_common/emoticons/icon_smile.gif

Grandville455

[thepontiacman]

I have 73,74,75 Grandville rearends, and many other parts. Let me know if I can help.

[email protected]

['ol Pinion head]

Grandville,
Next time you pull the axles, might count the splines on the axles. I should have a posi for the 2.93, just not sure if I have a 28 spline or 31 spline.

['ol Pinion head]

Michael, Hello there, regret missing this post earlier. The '71-73 (poss '74) Olds 98 share internal r/e parts with the '71-75 Riv & Buick 225. The BIG Buick guys swear by these 9 1/4's. I sure wish they came in a hsg with '65-72 style A-body upper perchs...def would have some fun cutting them down & swapping lower perchs on 'em!

Trying to remember from all the yarding "Safaris"... believe the '76 MP series was all by itself as all '76 MP series r/e had 28 spline axles with '71-76 style ring & pinion. Does that make sense to you? THX!!!

[grandville455]

Thats cool OPH, BUT I DONT THINK I WILL BE PULLING THEM ANYTIME SOON http://forums.performanceyears.com/groupee_common/emoticons/icon_frown.gif...ALSO LOOKING FOR THE REAR BUMPER FILLERS FOR HER TOO?IS THERE ANY OTHER WAY TO KNOW WHAT REAR IT HAS ITS GOT THE BIG DRIVESHAFT WITH THAT HUGE KNUCKLE ASSEMBLY IN THE REAR ON IT IF THAT HELPS COULD MAYBE TAKE A PIC FOR YOU TOO?
THANKS

Grandville464