1. Safety Precautions:
- Park the semi truck on level ground and engage the parking brake.
- Wear proper safety gear, including gloves and eye protection.
2. Jack Up the Truck:
- Using appropriate jack stands, raise the front or rear of the truck (depending on where you're adjusting brakes) until the wheels are off the ground.
3. Locate the Slack Adjusters:
- Find the slack adjusters near the brake chambers on the axles. They are usually cylindrical or hexagonal in shape.
4. Manual Adjustment:
- Some slack adjusters have a manual adjustment mechanism that requires a wrench. Turn the adjuster clockwise to extend the pushrod and tighten the brakes.
5. Automatic Adjustment (if available):
- Newer trucks often have automatic slack adjusters that adjust as needed during vehicle operation. Check if your truck has this feature.
6. Check for Proper Brake Adjustment:
- Rotate the wheel while observing the brake shoes or pads. Ensure there's a slight drag on the brake drum/rotor but not too much that it causes the wheel to lock.
7. Test Drive:
- After adjusting the brakes, take the truck for a short test drive and perform some controlled stops. Check for even braking and no pulling to one side.
8. Repeat for Other Brakes:
- If adjusting the front brakes, repeat the process for the other side. For rear brakes, adjust both sides simultaneously.
Note:
- Brake adjustment procedures may vary among different semi-truck models and manufacturers, so it's essential to consult your truck's service manual or seek guidance from a qualified technician. Brakes are a critical safety feature, and improper adjustments can compromise the vehicle's performance and safety.
- Brake adjustments might only temporarily solve the issue. In some cases, worn-out brake linings, drums, rotors, or other components may need replacement. Regular maintenance and inspections are crucial to ensure the semi-truck's brakes remain in good condition.
