How to Replace Crankshaft Pulley 88-98 GMC Sierra K1500
Difficulty: Intermediate · About 75 min · Gmc Sierra K1500
Replace the crankshaft pulley on a 1988–1998 GMC Sierra K1500 by removing the fan shroud, fan clutch, and serpentine belt, then installing the pulley and restoring the belt routing.
Tools you will need
- Adjustable Wrench
- Socket Extensions
- Flat Blade Screwdriver
- Torque Wrench
- 3/8 Inch Drive Ratchet
- 3/8 Inch Impact Gun
- Complete Metric Socket Set
Parts and supplies
- Crankshaft pulley
- Serpentine belt
Steps
Remove the fan shroud
Release the wiring retainer from the shroud and move the harness clear. Remove the shroud fasteners and lift the panel out carefully without striking the radiator.
Remove the fan clutch
Use the correct fan clutch wrench and hold the water pump pulley using an approved method. Loosen the clutch nut in the correct direction for this engine, then spin the fan and clutch out of the shroud.
Remove the serpentine belt
Record the belt routing from the underhood diagram. Rotate the tensioner with the correct drive tool, slip the belt off a pulley, and release the tensioner slowly before removing the belt.
Remove the crankshaft pulley
Remove the pulley retaining bolts and the center fastener. Support the pulley as it comes free and inspect the crankshaft nose, keyway, and mounting face for damage.
Install the replacement pulley
Align the pulley with the crankshaft locating feature and seat it without hammering on the crankshaft. Install the center fastener and pulley bolts, tightening them to the vehicle's specified torque and sequence.
Reinstall and check the belt
Route the belt according to the diagram and release the tensioner gradually. Check that every rib is centered in its pulley groove and that the belt tracks straight when the engine is turned by hand.
Reinstall the fan and shroud
Reinstall the fan clutch and secure it using the specified procedure. Fit the shroud, tighten its fasteners, and clip the wiring back into its original retainer.
Check pulley operation
Start the engine and observe the pulley and belt from a safe distance. Shut the engine off immediately if the pulley wobbles, the belt walks off center, or the fan contacts the shroud.
Check your vehicle’s repair manual for exact specifications and fit.