Installing a new transfer case motor on your 1999 GMC truck should be a straightforward process, but sometimes problems arise that can leave you feeling frustrated. This article will explore common 99 GMC transfer case motor install problems and provide you with the information needed to troubleshoot and fix them.
1999 GMC Transfer Case Motor Location
Common 99 GMC Transfer Case Motor Install Problems
Several issues can arise when installing a new transfer case motor on your 1999 GMC truck. Here are some of the most frequently encountered problems:
1. Improper Alignment
One of the most common installation errors is misaligning the transfer case motor with the transfer case itself. This can prevent the motor from engaging correctly and lead to difficulty shifting between 2WD and 4WD.
Solution: Carefully align the motor according to your truck’s specific make and model. Reference your owner’s manual or a reputable repair guide for precise instructions.
2. Electrical Issues
Faulty wiring, a blown fuse, or a malfunctioning switch can disrupt the electrical signals needed to operate the transfer case motor.
Solution:
- Check the fuse: Locate the fuse associated with your transfer case motor (refer to your owner’s manual) and inspect it for any breaks. Replace if necessary.
- Inspect wiring: Examine the wiring harness connecting the motor for any damage, such as fraying, cuts, or loose connections. Repair or replace any damaged wires.
- Test the switch: Use a multimeter to test the functionality of the 4WD switch. If the switch is faulty, it will need to be replaced.
Wiring Diagram for a 1999 GMC Transfer Case Motor
3. Encoder Motor Problems
The encoder motor provides feedback to your truck’s computer about the position of the transfer case shift motor. If the encoder motor fails, it can cause communication errors and prevent proper 4WD engagement.
Solution:
- Inspect for Damage: Check the encoder motor for any visible signs of damage, such as cracks or broken parts.
- Test for Continuity: Use a multimeter to test the encoder motor’s resistance and ensure it falls within the manufacturer’s specifications. If the resistance is outside the specified range, the encoder motor will likely need to be replaced.
4. Mechanical Binding
Sometimes, mechanical components within the transfer case, such as the shift fork or the mode fork, can become stuck or bind, preventing the motor from properly engaging.
Solution:
- Check for Obstructions: Inspect the area around the shift fork and mode fork for any debris or foreign objects that may be obstructing movement.
- Lubricate Components: Ensure all moving parts within the transfer case are adequately lubricated. Consult your owner’s manual for the recommended lubrication type and procedure.
GMC Transfer Case Encoder Motor and Components
Conclusion
While installing a new transfer case motor on your 99 GMC truck can seem daunting, understanding these common problems and their solutions can save you time and frustration. Always refer to your owner’s manual and seek advice from a qualified mechanic if you’re unsure about any aspect of the installation process.
FAQs
Q: What are the symptoms of a failing transfer case motor?
A: Common signs include difficulty switching between 2WD and 4WD, a grinding noise when shifting, and a flashing 4WD light on your dashboard.
Q: Can I drive my truck with a bad transfer case motor?
A: While technically possible, it’s not recommended. Driving with a faulty motor can lead to further damage to your transfer case and other drivetrain components.
Q: How much does it cost to replace a transfer case motor?
A: The cost can vary depending on labor rates and the specific motor needed. Generally, you can expect to pay between $400 and $800 for parts and labor.
