GM Service Manual Online
For 1990-2009 cars only

The cab replacement procedure will vary depending upon the optional equipment on the vehicle. Some steps required due to optional equipment have been included, but be sure to check the vehicle for any special steps it may require. The following procedures are intended to be used only as a guide.

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

    Important: 

       â€¢ Tag all lines, wires, hoses and harnesses during removal for proper location during installation.
       â€¢ Block the wheels.

  1. Disconnect the negative battery cable. Refer to Battery Cable Replacement .
  2. Open the hood.
  3. Remove the grille. refer to Grille Replacement .
  4. Remove the left and the right headlamp assemblies. Refer to Headlamp Replacement .
  5. Recover the air conditioning refrigerant. Refer to Refrigerant Recovery and Recharging .
  6. Remove the air conditioning pipes and the brackets. Refer to Evaporator Hose Assembly Replacement (LG5) .
  7. Drain the coolant.
  8. Remove the heater hoses. Refer to Heater Pipes Replacement (LG5 Inlet ) or Heater Pipes Replacement (LG4 Inlet) .
  9. Remove the ground strap.
  10. Remove the main wire harness under the hood.
  11. Remove the clutch fluid pipe (if equipped).
  12. Disconnect the transmission control cables.
  13. Disconnect the parking brake cable. Refer to Park Brake Cable Replacement .
  14. Tilt the cab. Refer to Cab Tilting in General Information.

  15. Object Number: 215795  Size: SH
  16. Remove the air brake hoses (if equipped) or the linkage to the brake master cylinder.
  17. Remove the steering shaft at the steering gear. Mark the shaft and the gear in order to aid in reassembly. Refer to Lower Steering Shaft Assembly Replacement .
  18. Remove the cab lock cover.
  19. Fasten a rope securely to the cab lock. Use a hoist or chain block in order to keep the cab tilted.
  20. Remove the torsion bar levers.
  21. Remove the cab tilt support.
  22. Lower the cab. Refer to Cab Tilting in General Information.
  23. Remove each center pin by tapping with a hammer, while lowering the cab slowly.

  24. Object Number: 215784  Size: SH

    Notice: When the cab is being removed, ensure that the lifting straps are not wrapped around the door frames. Otherwise, damage to the window channels may occur.

  25. Perform the following procedure in order to remove the cab from the chassis. Keep in mind that the trimmed cab weighs about 1,000 lbs.
  26. 23.1. Use four commercial straps that are 6 inches wide and about 10 feet long in order to lift the cab from the chassis.
    23.2. Open the doors. Pass the straps into the cab through the door opening on each side through the rear of the cab.
    23.3. Connect the straps in the center.
    23.4. Close the doors.
  27. Walk around the cab in order to make sure all components have been disconnected from the chassis.
  28. Raise the cab slowly. Use the aid of a helper in order to guide the cab while the cab is being lifted.

Installation Procedure


    Object Number: 215784  Size: SH
  1. Block the chassis wheels.
  2. Notice: When the cab is being removed, ensure that the lifting straps are not wrapped around the door frames. Otherwise, damage to the window channels may occur.

  3. Perform the following procedure in order to install the cab onto the chassis. Keep in mind that the trimmed cab weighs about 1,000 lbs.
  4. 2.1. Use four commercial straps that are 6 inches wide and about 10 feet long in order to lift the cab from the chassis.
    2.2. Open the doors. Pass the straps into the cab through the door opening on each side through the rear of cab.
    2.3. Connect the straps in the center.
    2.4. Close the doors.

    Object Number: 215820  Size: SH
  5. Apply grease to the following areas of the cab mounts:
  6. • The circumference area of the bracket where the washer comes in contact
    • The bushing inner surface in the side where the sleeve is inserted
    • At least two areas on both inside surfaces of the bracket where the washer comes in contact

    Object Number: 215795  Size: SH
  7. Install the left and the right center pins.
  8. Perform the following procedure:
  9. 5.1. Hook a wire to the cab striker.
    5.2. Pull the safety lever.
    5.3. Tilt the cab slowly.
    5.4. Use the wire in order to keep the cab from floating up.

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Extend the cab support and lock it into position.
  11. Tighten
    Tighten the bolts to 68 N·m (50 lb ft).

  12. Perform the following in order to install the torsion bar levers.
  13. • Locate the left and right identification marks before installation.
    • Match the spline.
    • Install the torsion bar levers.

    Tighten
    Tighten the bolt/nut to 37 N·m (27 lb ft).

  14. Use the match marks made during disassembly as a guide in order to apply grease to the steering shaft.
  15. Insert the steering shaft on the steering unit. Refer to Lower Steering Shaft Assembly Replacement .
  16. Tighten the key bolt.
  17. Tighten
    Tighten the bolts to 61 N·m (45 lb ft).

  18. Connect the throttle cable.
  19. Connect the transmission cables. Refer to Shift Cable Replacement .
  20. Connect the air brake hoses (if equipped) or the linkage to the brake master cylinder.
  21. Connect the parking brake cable. Refer to Park Brake Cable Replacement .
  22. Lower the cab.
  23. Install the clutch fluid pipe (if equipped).
  24. Install the main wire harness under the hood.
  25. Install the ground strap.
  26. Install the heater hoses. Refer to Heater Pipes Replacement (LG5 Outlet) or Heater Pipes Replacement (LG4 Outlet ) .
  27. Install the left and the right headlamp assemblies. Refer to Headlamp Replacement .
  28. Install the grille. Refer to Grille Replacement .
  29. Connect the negative battery cable. Refer to Battery Cable Replacement .
  30. Recharge the air conditioning refrigerant to specification. Refer to Refrigerant Recovery and Recharging .
  31. Refill the engine coolant to proper level. Refer to Fluid and Lubricant Recommendations .
  32. Bleed the clutch system.