Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1563 (TRANSFER CASE - NVG 246-NP8 (TWO SPEED AUTOMATIC))REPAIR INSTRUCTIONSTRANSFER CASE INPUT SHAFT SEAL REPLACEMENTINSTALLATION PROCEDURE

2003 Chevrolet TrailBlazer 4.2 S, 4WD

Installation Procedure

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Installation Procedure

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

IMPORTANT: When installing the input shaft seal, make sure that the part numbers on the seal are facing outward (away from the body of the transfer case).

Align the transfer case input shaft seal evenly on the input shaft.
IMPORTANT: The input shaft seal should be even with the surface of the transfer case after installation.
Using the J 42738, install the transfer case input shaft seal.
Install the transfer case. Refer to Transfer Case Assembly Replacement .
Check the fluid level. Add fluid if necessary.

Fig 1: Install Transfer Case Input Shaft Seal Using J 42738
Courtesy of GENERAL MOTORS CORP.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.