PML GM 8½" and 8 5/8" Ring Gear, 10 Bolt Horizontal Fins, Differential Cover - CJC Off Road

PML GM 8½" and 8 5/8" Ring Gear, 10 Bolt Horizontal Fins, Differential Cover

Name: PML GM 8½ and 8 5/8 Ring Gear, 10 Bolt Horizontal Fins, Differential Cover
Brand: PML
SKU: 10815
Price: 255.0 USD
Availability: InStock

10815

$255.00

PML Finish

As-Cast

Black

Stock Bolt Size

8mm - 1.25x21

8mm - 1.25x16

5/16in - 18x7/8

5/16in - 18x5/8

Add machining of a 1/8 NPT hole for an aftermarket temperature sending unit

No machining

Yes add drilling and tapping of a 1/8 NPT hole

Quantity

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Click on the button under the bolt size you need to order the differential cover. Scroll down for more information on bolts.

General Information

Volume: 0.5 qt. over stock

Dimensions: See this pdf file, a separate window or tab will open

PML makes two differential covers for the GM 8 ½, 8 5/8 inch 10 bolt rear end. To see both options, go to both PML GM 8½" differential covers.

Applications for a PML GM 10 Bolt Differential Cover

This PML differential cover fits the rear end differential on many GM, GMC, and Chevrolet vehicles. Typical applications include the following. Be aware that for each model and year there may be more than one rear axle possible. See also GM 10 bolt 7.5 and GM 14 bolt 9.5.

½ Ton Trucks, 1979 to Current:

C10 & K10
C1500 & K1500
Silverado 1500
Sierra 1500

¾ Ton Trucks, 1979 to 1998:

C20 & K20
C2500 & K2500

½ Ton Vans, 1979 to Current:

Vandura
Express
Savana
G1500

¾ Ton Vans, 1979 to Current:

Vandura
Express
Savana
G2500

Full Size Blazer, 1977 to 1994

GMC Jimmy, 1977 to 1991

Escalade, Tahoe & Yukon, 1992 & newer
(check for panhard bar)

Avalanche 1500

Suburban 1500, 1982 to current

Hummer H3

GM 8.2 10 Bolt: These rear end covers can also fit on older vehicles with the GM 8.2 differential. For example:

1966 Impala
1960s Chevelle
1966 Pontiac GTO

See our GM 8.2 web page for more information.

PML GM 8.5 cover and stock GM 8.2 cover

4WD Front Applications: Note that these covers will not fit the front axle 10 bolt 8 1/2" ring gear differential found on some 4WD Chevy and GMC SUVs and trucks.

Temperature Sensor Port Option

The boss on the side can optionally be machined for temperature sensor for $40 additional (call to order machining and let us know your sensor thread size).

Bolt Information

PML includes mounting bolts with all differential covers. PML provides bolts that are longer than the stock bolts since the flange on PML's cover is much thicker than stock. The bolts with the stock cover will not work.

GM has used four different bolts on these differentials so to complete your order, we need to know which bolts you have. These differentials have used both metric and standard cover bolts. The bolt length has not been consistent either. When ordering one of these covers, you will need to pull one of your stock bolts out (a top bolt is best) and measure the length and determine whether it is metric or standard.

Bolt length is measured from the underside of the head (where a washer would sit) to the tip. If the bolts are metric, the length will be 21mm or 16mm. If the bolt is standard, the length will be 5/8 inch or 7/8 inch.
Metric bolts will have 20 threads per inch, standard ones will have 18. Also, a bolt head with lines or letters on it is typically standard. A bolt with numbers such as 5.8, 9.8, 10.9, or 12.9 is likely to be metric.

We know this is a hassle, but we do not want to send the wrong bolts or charge everyone a lot of extra money to cover sending all possible bolts with each cover.

Gasket Information for a PML GM 10 Bolt Differential Cover

PML machines the gasket surface of our differential covers completely flat. The flange surface of the differential housing is also machined flat. A thin bead of RTV silicon sealant makes an excellent seal between two machined surfaces. If you prefer to use a gasket, we have had customers recommend the Fel-Pro RDS 55028-1 gasket.

Installations

Chevy Suburban 1500 4x4, Z71, 2010

The images below are of Mark & Tahoe's 2010 Z71 Suburban. Our thanks to them for emailing us the pictures. They also commented on the cover: "Fit perfect! Thank you very much!!!"

From left to right: 2010 Suburban, Stock Cover, PML Cover Installed
Click on image to view larger.

Yukon, 2005


	PML differential cover installed on a 2005 GMC Yukon SLE. The finish on this differential cover is black powder coat. Our thanks to Scott for sending us the picture. Click on image to view larger.

Silverado 1500


	PML differential cover installed on a Chevrolet Silverado 1500. The finish on this differential cover is black powder coat. Click on image to view larger.

Cadillac Escalade EXT, 2011

Michael installed a polish finish PML differential cover on his Escalade. He put 3 coats of clear coat on it and jb welded a filter magnet to the inside which has 25lbs of holding strength. (Note that we at PML do not think the magnet is needed or necessarily a good idea since a magnet attached incorrectly could cause a lot of problems.) Michael removed some fin material since he had about 1/4" clearance and wanted to be safe if the rubber bushings flexed. Our thanks to Michael for all his feedback and pictures.

For a larger picture, please click one of the above images. A separate window will open showing a bigger picture. (The larger pictures take a minute to display.)

PML Differential Cover Features:

Increased oil capacity for cooler temperatures
Sand-cast aluminum with raised fins
3/16-inch thick wall construction to add strength to differential housing
3/8-inch thick gasket flange will not bend when bolts are tightened
Machined gasket surface for a secure seal using RTV or factory reusable gasket
Oil changes without removing the cover
All hardware provided, including magnetic drain plug

Learn more about finishes and construction of PML parts.