Yukon Gear Master Overhaul Kit for AMC Model 20 Rear Differential

Yukon YK M20 AMC Model 20 Rear Differential Complete Rebuild Kit

The YK M20 from Yukon Gear and Axle is the purpose-built master overhaul kit for the AMC Model 20 rear differential used in Jeep CJ and Wrangler models, American Motors vehicles, and specialty applications including the Hummer H1. When your Model 20 axle needs new bearings, seals, or a full rebuild, the YK M20 delivers every component for a thorough complete rebuild kit in a single package. Timken bearings, a full shim set, all seals, and complete hardware are included. The YK M20 is the go-to solution for rebuilding this classic American rear differential.

Features and Benefits

• Purpose-built for the AMC Model 20 rear differential in Jeep CJ, early Wrangler, and AMC vehicles
• Timken carrier bearings and races for superior load capacity and durability
• Timken pinion bearings and races for accurate pinion depth and quiet operation
• Complete pinion depth shim set for correct gear mesh and contact pattern
• Complete carrier shim set for proper backlash and bearing preload
• Pinion seal and axle seals to prevent fluid loss
• Ring gear bolts, pinion nut, and crush sleeve for a complete hardware refresh
• Gear marking compound with brush and thread-locking compound included
• Differential cover gasket for a leak-free seal
• Compatible with OEM and aftermarket ring and pinion gear sets
• All components quality-verified to Yukon Gear standards

Vehicle Fitment

Specifications

What Is Included

• Timken front carrier bearing and race
• Timken rear carrier bearing and race
• Timken inner pinion bearing and race
• Timken outer pinion bearing and race
• Pinion seal
• Axle seals (pair)
• Complete pinion depth shim set
• Complete carrier shim set
• Ring gear bolt set
• Pinion nut
• Crush sleeve
• Thread-locking compound
• Gear marking compound with brush
• Differential cover gasket

Frequently Asked Questions

What vehicles use the AMC Model 20 rear differential?
The Model 20 was used in Jeep CJ5, CJ7, Scrambler, and J-series trucks, as well as American Motors Javelin, AMX, Matador, and Pacer models, and early Hummer H1 applications. The YK M20 provides everything needed to rebuild this axle properly.

Does the YK M20 include Timken bearings?
Yes. The YK M20 includes Timken carrier bearings with races and Timken pinion bearings with races for industry-leading durability.

Can this kit be used with aftermarket ring and pinion gears?
Yes. The complete shim set in the YK M20 allows proper setup with both OEM replacement and aftermarket gear ratios.

Is a differential cover gasket included?
Yes. A differential cover gasket is included in the YK M20 kit for a complete rebuild.

Does this kit fit the Hummer H1?
Yes. The YK M20 covers 2002-2006 Hummer H1 models equipped with the Model 20 rear differential. Verify differential type before ordering.

Will installing the YK M20 void my vehicle warranty under the Magnuson-Moss Warranty Act?
Under the Magnuson-Moss Warranty Act, a vehicle manufacturer cannot void your warranty solely because an aftermarket part was installed. The warranty is voided only if the manufacturer proves the part caused the specific failure. Consult your warranty documents and a qualified professional.

What warranty does Yukon Gear offer?
Yukon Gear and Axle provides a limited warranty on the YK M20 covering defects in materials and workmanship. Contact Yukon Gear for full terms.

Is professional installation recommended?
Yes. Precision pinion depth, backlash, and bearing preload settings are essential. A qualified drivetrain technician is strongly recommended.

Installation Instructions

1. Raise and support the vehicle on jack stands. Drain differential fluid.
2. Remove the rear driveshaft from the differential flange.
3. Remove the differential cover and clean all mating surfaces.
4. Mark bearing caps and housing for correct reinstallation orientation.
5. Remove carrier bearing caps and extract the carrier assembly.
6. Press old carrier bearings off the carrier and discard with races.
7. Remove the pinion nut and flange, then drive out the pinion shaft.
8. Press out old pinion bearings and remove the pinion seal.
9. Clean all bearing bores and housing surfaces thoroughly.
10. Press new Timken pinion bearing races into the housing.
11. Determine correct pinion shim and install new inner pinion bearing and shim on the pinion shaft.
12. Install new crush sleeve and outer pinion bearing. Install new pinion seal. Thread on pinion nut and torque to specification while monitoring rotating torque.
13. Press new Timken carrier bearings onto the carrier. Install carrier with correct shims to achieve specified backlash.
14. Verify gear contact pattern with marking compound. Adjust shims as needed.
15. Torque bearing caps to spec. Install new gasket and cover, fill with correct gear oil, reinstall driveshaft, and lower the vehicle.

Proposition 65 Warning: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.p65warnings.ca.gov.