Valve Clearance: Adjustments

Valve Clearance Adjustment

1. Remove the engine cover. Refer to Engine Cover Replacement .
2. Remove the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement (4.3L, 4.8L, 5.3L, 6.0L, 6.2L, 7.0L) (Service and Repair)Engine Coolant Fan Upper Shroud Replacement (6.6L) (Service and Repair) .




3. Remove the fan clutch. Refer to Fan Clutch Replacement (Service and Repair) .
4. Remove the upper valve rocker arm covers. Refer to Valve Rocker Arm Cover Replacement - Upper Left Side (Valve Rocker Arm Cover Replacement - Upper Left Side) and Valve Rocker Arm Cover Replacement - Upper Right Side (LMM) (Valve Rocker Arm Cover Replacement - Upper Right Side (LMM)) .
5. Rotate the crankshaft in order to bring the number 1 cylinder to top dead center (TDC) of the compression stroke. The number 1 cylinder is the front cylinder on the right bank. The mark on the crankshaft balancer should be aligned with the mark on the engine.




6. Loosen the valve adjusting screws.
7. Insert a feeler gage between the tip of the rocker arm and the valve bridge.




8. Adjust the valve lash to 0.3 mm (0.012 in). Refer to Valve Clearance Adjustment Specifications (Specifications) to determine which valves can be adjusted when the engine is at TDC.

Notice: Refer to Fastener Notice .

9. Tighten the lock nut.

Tighten nut to 22 N.m (16 lb ft).





10. Rotate the crankshaft one revolution in order to bring the number 1 cylinder to TDC of the exhaust stroke.




11. Loosen the valve adjusting screws.
12. Insert a feeler gage between the tip of the rocker arm and the valve bridge.




13. Adjust the valve clearance to 0.3 mm (0.0112 in). Refer to Valve Clearance Adjustment Specifications (Specifications) to determine which valves can be adjusted when the engine is at TDC.
14. Tighten the lock nut.

Tighten nut to 22 N.m (16 lb ft).

15. Install the upper valve rocker arm covers. Refer to Valve Rocker Arm Cover Replacement - Upper Left Side (Valve Rocker Arm Cover Replacement - Upper Left Side) and Valve Rocker Arm Cover Replacement - Upper Right Side (LMM) (Valve Rocker Arm Cover Replacement - Upper Right Side (LMM)) .
16. Install the fan clutch. Refer to Fan Clutch Replacement (Service and Repair) .
17. Install the upper fan shroud. Refer to Engine Coolant Fan Upper Shroud Replacement (4.3L, 4.8L, 5.3L, 6.0L, 6.2L, 7.0L) (Service and Repair)Engine Coolant Fan Upper Shroud Replacement (6.6L) (Service and Repair) .
18. Install the engine cover. Refer to Engine Cover Replacement .