Chevrolet Silverado / GMC Sierra. Service manual — part 866

Fig. 91: Driving Seal Into Seal Bore
Courtesy of GENERAL MOTORS CORP.

2. Slide J 43772 over the turbine shaft and the stator shaft until the seal starts into the seal

bore. See Special Tools. Strike the J 43772 with a mallet (1) to drive the seal into the seal
bore. See Special Tools. The seal is installed correctly when the shoulder of the J 43772
squarely contacts the outer surface of the oil pump. See Special Tools.

3. Install the torque converter into the transmission. Refer to Torque Converter

Replacement.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

REAR PROPSHAFT SHAFT SEAL REPLACEMENT

Tools Required

J 24171-A Seal and Dust Shield Remover

J 43782 Rear Seal Installer. See Special Tools.

Removal Procedure

Fig. 92: Removing Rear Seal Using The Slide-Hammer
Courtesy of GENERAL MOTORS CORP.

1. Remove the yoke assembly from the transmission. Refer to Output Flange/Yoke

Replacement.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

2. Obtain J 24171-A and install a 90 degree hook onto the end of the slide-hammer (1).

3. Position the 90 degree hook behind the rear face of the seal's outer case (2).

4. Remove the rear seal using the slide-hammer.

5. Inspect the seal bore for scratches. Remove any scratches in the seal bore using crocus cloth.

Installation Procedure

Fig. 93: Aligning Rear Propshaft Seal Lip Outward Onto J 43782
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Be sure the new seal has blue sealant coating the OD (4).

This identifies the seal for use in the 1000 Series
transmissions. The blue sealant identification is important

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

1. Align the seal so the seal lip (2) is outward and the face of the steel case (1) will be against

the driving face (3) of the tool. Install the new seal onto J 43782 . See Special Tools.

Fig. 94: Installing Rear Propshaft Seal
Courtesy of GENERAL MOTORS CORP.

2. Slide J 43782 over the output shaft until the seal enters the seal bore. See Special Tools.

Strike J 43782 with a mallet (1) to drive the seal into the seal bore. See Special Tools. The

because the 1000 Series transmissions have an overdrive
ratio in fifth range and there is a potential for high output
shaft speeds and resultant high seal temperature.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Automatic Transmission - Allison - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado