GM AAM 9.5, 9.76 12 Bolt Rear
Part Number 11129

Volume: 0.6 quarts over stock, approximately

Dimensions: Click here for dimensions.

Number of Bolts: 12 bolts

PML designed this rear differential cover for 2014 and newer Chevy Silverado and GMC Sierra 1500 trucks, vans and SUVs. Some 2019 and newer models may have newer GM 9.5 differential, see the APPLICATIONS section.

Benefits:

• Heavy duty construction
• Extra capacity
• Fins for cooling
• Drain hole and magnetic drain plug for easy servicing
• New mounting bolts included
• Works with Duragrip and similar aftermarket carriers when changing to 4.10 or deeper gears, no spacer needed

This PML 12 bolt GM AAM differential cover is designed to replace the stock cover. 2019 and newer models may be able to use this cover or may have the newer GM 9.5 axle, see PML part number 11172.

Examples of vehicles that commonly have used this differential cover:

• 2014 to 2018, some 2019 and newer, Silverado 1500
• 2014 to 2018, some 2019 and newer, Sierra 1500
• 2014 to 2018, some 2019 and newer, GMC/Chevy SUVs (modifications needed for Escalade, Suburban, Tahoe, Yukon!)
• 2018 and newer Express and Savana Vans (check for clearance)

Always check your vehicle to verify configuration and clearance. Configurations vary.

GM OEM gasket: The GM OEM part number for the gasket that corresponds to this cover is 22943110.

Aftermarket Carriers: Cover works without spacer with Duragrip and many aftermarket carriers, which are required when changing to 4.10 or deeper gears. See Installations for an example.

Installation Note: Bracket for parking brake cable probably needs to be slightly moved or bent.

Modifications for SUVs (Escalade, Suburban, Tahoe, Yukon) and Similar:

• 2014 and newer Escalade, Suburban, Tahoe, and Yukon usually have a sway bar behind the stock cover that is very close to the stock differential cover. This cover has been modified to fit. See Installations for examples on Tahoe SUVs.
• PML can modified the cover for a custom machining charge. Call for details.
• If vehicle is lifted or has aftermarket sway or panhard bars, this cover may fit without modification.

2019 and newer models: May use a similar 12 bolt rear cover that is slightly larger and not compatible with this cover. To figure out which you have, try checking the OEM gasket part number or visually comparing your cover to the pictures below.

• To check gasket part number:
  Find out (call dealer, look on line) for the OEM gasket part number.
  This PML differential cover, part number 11129, works with gasket GM AC Delco part number 22943110.
• To check visually look near the fill/level check hole.
• The FIRST image shows 2014 and newer stock cover for GM AAM 9.5, 9.76 and this PML Part Number 11129 is the replacement cover.
• The SECOND image shows the stock cover for new GM 9.5 2019 and newer vehicles and PML Part Number 11172 is the replacement cover for that.
  
      
  Click on image to view larger. For example, note that the area around and below fill hole is different.

For the newer cover, see PML Part Number 11172.

Tow Package: Trucks with the optional tow package usually include the 9.76 inch ring gear differential. These cover is the same.

Our thanks to those who have emailed us their comments and pictures.

• 2023 Express 3500 6.6


• 2018 Silverado 1500
• 2017 Silverado 1500 5.3
• 2016 Silverado 1500 5.3 Lifted
• 2015 Silverado 1500 6.2L
• 2014 Silverado 1500 with Aftermarket Gears
• 2014 Silverado 1500 with Hellwig Sway Bar
• 2014 Silverado 1500 No Tow Package
• 2014 Silverado 1500 Max Trailering Package
• 2014 Silverado 1500 4wd 5.3L


• 2017 Sierra


• 2016 Tahoe 5.3L With Tow Package
• 2015 Tahoe 5.3L With Tow Package

2023 Chevy Express

Brent installed this PML differential cover on his 2023 Chevy Express 3500 6.6L van. He had no fitment issues and did not remove the spare tire.

PML 9.5 differential cover installed on a 2023 Chevy Express   close up of PML differential cover   Click on image to view larger in a new tab or window.

2018 Silverado 1500

Jim installed this PML differential cover on his 2018 Chevy Silverado 5.3L with 11" lift and 38 x 13.50 Nitto Trail Grapplers.

2018 Silverado 1500   Stock Cover   PML cover   PML cover 2
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2017 Silverado 1500 5.3

Mark installed this PML differential cover on his 2017 Silverado 1500 LT 5.3 V8.

2017 Silverado 1500 LT   truck with trailer   PML cover installed
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2016 Silverado 1500 5.3 Lifted

Chad installed this PML rear differential cover on his 2016 1500 5.3 V8 truck with a 4 inch lift, Flowmaster air intake and FlowFX exhaust. He emailed us that the installation was easy and he loves the cover.

PML differential cover has a custom polish finish, not available from PML.

PML differential cover installed on 2016 Silverado 1500 5.3 Lifted   OEM rear differential cover   PML cover installed
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2015 Silverado 6.2L

Rich installed this PML differential cover on his 2015 Chevy Silverado 6.2L and used ARP 12 point fasteners.

2015 Silverado   Stock Cover   PML Cover  
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2014 Silverado 1500 with Aftermarket Gears

Yukon Gear tested this PML cover with their 9.5 Duragrip aftermarket carrier. The stock cover requires a spacer or modification because of clearance issues with aftermarket carriers, such as Duragrip. Aftermarket carriers are required when changing to 4.10 or deeper aftermarket gears. The PML cover does not need a spacer. This will benefit customers doing the following:

• Adding an aftermarket limited slip carrier to stock gears
• Changing gear ratios and using an aftermarket carrier

  
Blue putty indicates where stock cover has clearance issues. PML cover had no issues. Click on image to view larger.

Yukon Gear reported that "The PML cover has more than enough clearance and will require no modification." They used blue putty to check clearance. The PML cover has around .250” clearance between the gear and the carrier to the cover. This was without the gasket installed. The closest point of contact appears to be the outside edge of the carrier caps. Mainly the left hand side, but there was still around an 1/8” or more of clearance.

2014 Silverado 1500 with Hellwig Sway Bar

This truck is a 2014 Chevrolet Silverado 1500 4WD Regular Cab 119.0" LT with a 2LT 5.3L/325 8 Cylinder Engine. The stock sway bar was replaced with a Hellwig sway bar and the stock rear differential cover was replaced with this PML rear differential cover. There was plenty of room to remove the stock cover and install the PML cover without removing the Hellwig sway bar.

     
      Click on an image to view larger.

2014 Silverado 1500 No Tow Package

Andrew installed PML's 12 bolt Chevy rear cover on his 2014 Chevrolet Silverado 1500 5.3. His truck does not have the optional factory tow package ("max trailering package").

Andrew needed to slightly bend the bracket for the emergency brake line to keep the cable from rubbing on the PML cover.

     
Click on image to view larger.

2014 Silverado 1500 Max Trailering Package

John installed this PML differential cover on his 2014 Silverado 1500 5.3L with the factory Max Trailering Package. The Max Trailering Package includes a slightly larger 9.76 inch ring gear on the rear differential. The stock cover and the PML cover are the same for 9.5 inch ring gear or the 9.76 inch ring gear.

     
Click on image to view larger.

2014 Silverado 1500 4wd 5.3L

Viktor installed this PML differential cover on his 2014 Chevrolet Silverado 1500 5.3L 6L80 LTZ 4x4. He also installed GM PML transmission pan P/N 11025

PML cover   PML Pan
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2017 Sierra

These images are from 2017 GMC Sierra 1500 trucks with this PML rear differential cover. These trucks are customized with aftermarket parts and paint.

PML cover on 2017 GMC Sierra show truck   2017 Sierra show truck, right side   2017 Sierra show truck with PML cover
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2016 Tahoe 5.3L With Tow Package

Brian had PML machine off the top of this PML cover to add clearance for the pan hard and sway bar on his 2016 Tahoe with the tow package. Brian needed to remove a little more material from the top of the 3rd and 4th fins and it is a still tight fit.

Brian also installed a PML 6L80 transmission pan on his Tahoe (2nd picture).

PML cover on 2016 Tahoe   PML 6L80 transmission pan on 2016 Tahoe with tow package   PML cover modified for 2016 Tahoe with tow package   Modification to PML cover to add clearance
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2015 Tahoe 5.3L With Tow Package

Eddie contacted us about his 2015 Tahoe with the GM 9.5 inch rear, 12 bolt cover, 3.55 gears, locking differential and 33 spline axles. The Tahoe has sway and pan hard bars right behind the stock cover.

The PML cover is about 0.35 inches deeper than stock. There is about 0.40 inches to the sway bar on the Tahoe. After removing 0.40 inches off the top of the PML cover, Eddie sprayed it with high temp glossy black and installed the PML cover.

Read Eddie's Installation Notes. Our thanks to Eddie for his write-up and info!

2015 Tahoe 5.3 factory tow package stock rear differential cover.   2015 Tahoe 5.3 with a modified PML differential cover installed.   PML 12 bolt 9.5, 9.76 differential cover modified to clear the sway bar on a 2015 Tahoe.
Clearance from stock rear differential cover to sway bar on a 2015 Tahoe.   Clearance from modified PML cover to sway bar on a 2015 Tahoe.   Click on any image to view larger.

Optional Temperature Sensor Machining

This differential cover has an undrilled boss for an aftermarket temperature sending unit. Optionally, PML can drill and tap a 1/8 NPT hole. The boss is located on the side below the fill hole.

Stock Covers

These are pictures of the stock cover for 2014 Silverado 1500s.

• The cover on the left is from a 2014 Silverado 1500 5.3L Crew Cab.
• The cover on the right is from a 2014 Silverado 1500 6.2L Crew Cab with the Trailer Package and the 9.76 rear end.

  
Click on image to view larger.

Inside of PML Cover

 Click on image to view larger.

The PML differential cover follows the same general shape of the stock cover. The interior is mostly smooth.

Space for the extra capacity is at the bottom

Comparing PML Cover to Gasket from 2019 Silverado

Some 2019 and newer trucks have a slightly larger GM 9.5 rear differential cover. The gasket for a 2019 Silverado 1500 is shown compared to this PML differential cover.

PML Differential Cover Compared to Stock

 
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