[LouisianaGuy]

What is the best way to tell the difference between a chevy/Gm 7.5, 8.2, 8.5, and the 8.8.
and will gears from any of these rears interchange?
Mike

[LouisianaGuy]

What is the best way to tell the difference between a chevy/Gm 7.5, 8.2, 8.5, and the 8.8.
and will gears from any of these rears interchange?
Mike

['ol Pinion head]

GM A-body rearends 64+

-7.5 10-bolts have 2.5" diam axle tubes. Straps & bolts holding u-joints. 26 spline c-clip axles... whole rearend is super weak. Shock mounts will angle out to the center section of the tires & make wide tire selection no fun. Only avail from '78-87. can be finagled in a '72 or earlier A-body to roll the car around.

-8.2 Chevy 10-bolt, c-clip design axle retention (no bolt in axles)& are weak. Rear cover will have splash lip similiar to a 12 bolt Chebby. Pinion yoke will accept spicer 1310 with U-bolts & nuts. The 8.2 Chebby 10 bolts are basically good to stick under parts cars to push them around...

-8.2 Buick 10-bolt. In early years ('64-65) same as Pontiac & Olds 8.2. By '68, Buick engineers changed housing to accept bigger pinion bearing & race. This is when the 3.42 & 3.64 gears came about. Used the same carrier as Pontiac, but not the same Ring & Pinion or axles. Bigger pinion bearing, hmmm...what else could have bigger pinion bearings

-8.2 Pontiac rearend has bolt in axles & U straps & nuts to hold the the u-joint in. Toughest ones will have N on the front of the case (68-70), tough to find. Nodular iron case prevented case flex to much higher degree than common grey iron case. The nodular cased HD Safe-T-Tracks originally had the best axles- hot forged...All others had std duty axles.

-Type "O" Olds 442-Cutlass 10 bolt (8.5 diam ring gear). First used in '66. 12 bolt smooth cover, 10 bolts holding ring gear to carrier. Available in 28 spline from '66-67 & available in both 28 spline & HD 31 spline bolt in axles from 68-70. Again U bolts & nuts for u-joint retention. In 31 spline, one tough rearend. Also TOUGH to find parts for Have to buy new Moser axles if you need 31 spline axles. This rearend is where the modern 8.5 corporate can trace it's roots.

-12 bolt 8.875 Chebby car avail from '65-72 in two different widths (65-67 & 68-72) for A-bodys. 12 bolt cover with big splash lip. C-clip axles (not bolt in). Also two different pinion flanges, most common is "small chebby" Spicer 1310. High horse L78's & LS6's got stronger axles & bigger Spicer 1330 pinion flange.

-8.5 corporate 10 bolt A-body. Staps & bolts holding u-joint in. Bolt in axles, tapered axle bearings [img]smile.gif[/img] Two different early sized bolt-in axles for 3 different housings. Actually 5 different A-body housings over the years. One version of '73-77 8.5 A-body is c-clip. Fortunately, most GP'S, GrandAm's, & LeMans of this era ('73-77) had bolt in axles.

-Lastly, while not an A-body rear, the '85-87 G body 8.5 corporate 10 bolt was also built for GN's, T-types, & 442's. This is same width as weak 7.5 A-G series, has small housing tubes, & c-clip axles.

Other than 8.2 chebby gears being able to be adapted into 8.2 Pontiac rears, gears will not interchange between different R/E series.

[LouisianaGuy]

I got one word for ya "WOW" im impressed, see that is what i love about these forums nothing but a wealth of knowledge [img]smile.gif[/img] Thanks now i know
Mike