We have one of these in the polish finish on SPECIAL. This is a cover we modified here for a customer who changed his mind.

The GM 8.2 inch rear differential cover is very similar to the GM 8.5, 8.6 differential cover. The bolt pattern is almost the same. About half the bolt holes line up. The other half are close but 1/8 to 1/4 inch off. PML 8.5, 8.6 covers have been modified to fit an 8.2 differential.

Note: Information is for reference only, not recommended or supported by PML. Once modified a cover cannot be returned.

Applications

Some Chevrolet, Buick, Oldsmobile and Pontiac 1960s and 1970s muscle cars have this differential.

• Chevelle
• Impala
• Monte Carlo
• Nova
• Oldsmobile Cutlass
• Pontiac GTO

Some vehicles may have a 8.2 or an 8.5 or an 8.875, depending on configuration. GM began using the 8.5 around 1970. The GM 8.875 inch ring gear has 12 bolts while the 8.2 and 8.5, 8.6 have 10 bolts.

A customer recommended Felpro Gasket RDS 13410 for a GM 8.2 differential. Since the size, shape and bolt hole pattern of the 8.2 and 8.5/8.6 are nearly identical, a gasket is an easy way to check if a differential has the 8.2 inch ring gear or the 8.5/8.6 inch ring gear. If the bolt hole pattern on Fel Pro Gasket RDS 13410 lines up with the bolt hole pattern on your differential, it would be an 8.2. If several holes do not completely line up but are close, then the differential is probably a GM 8.5/8.625 inch ring gear.

Our customers have reported that the bolts used the GM 8.2 have been 5/16-18 x 7/8 inch.

Modified PML GM 8.5, 8.6 Differential Covers

These are pictures of PML GM 8.5, 8.6 differential covers that have been modified to fit a GM 8.2 differential. Several of the bolt holes have been enlarged. The first 2 pictures show PML Part Number 6082 in the cast finish and the second 2 pictures show PML Part Number 10815 in the black powder coat finish. If you click on the smaller images, you can see that some of the bolt holes have been enlarged.

     
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These are a pictures of stock 8.2 cover from a 1966 Pontiac GTO and a PML cover that has been modified for the 8.2 differential. Note that other 8.2 stock covers look different. The modified PML cover was installed on a 1965 GTO.

 
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