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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 GMC T-Series Medium Duty Truck F6/F7/F8 🢒 Bulletins 🢒 Engine Overheats, Temperature Gauge Reads Hot, Audible Warning Alarm Sounds, Check Gauge Lamp On, (Replace Cooling Fan Blade, Fan Clutch and Radiator Shroud)

Engine Overheats, Temperature Gauge Reads Hot, Audible Warning Alarm Sounds, Check Gauge Lamp On, (Replace Cooling Fan Blade, Fan Clutch and Radiator Shroud)

Subject:Engine Overheats, Temperature Gauge Reads Hot, Audible Warning Alarm Sounds, Check Gauge Lamp On (Replace Cooling Fan Blade, Fan Clutch and Radiator Shroud)

Models:1999-2002 Chevrolet and GMC 6-7F T-Series Medium Duty Tilt Cab Models
with Isuzu Diesel Engine (VIN 3 -- RPO LG4)


Condition

Some customers may comment on one or more of the following conditions:

    • Engine Overheats
    • Temperature Gauge Reads Hot
    • Audible Warning Alarm Sounds
    • Check Gauge Lamp On

Cause

The fan clutch may not engage quickly enough to cool the engine before the vehicle exceeds the top tank temperature.

Correction

Replace the cooling fan blade and clutch. For models equipped with manual transmission and those equipped with 622 mm (24½ in) fan blade, replace the radiator fan shroud also. Use the procedure and part numbers listed below.

  1. Tilt and secure the cab.
  2. Install the J 38426 (Pulley Strap Wrench) around the fan pulley to secure.
  3. Install the J 38425 (Fan Hub Wrench) to the fan clutch nut.
  4. Remove the fan blade/clutch assembly from the vehicle.
  5. Remove the bolts and washers securing the fan blade to the fan clutch.

    6. Important: For models equipped with manual transmission and/or a 622 mm (24½  in) fan blade, proceed to step 6. All others proceed to step 16.

  6. Partially drain the cooling system just below the upper radiator hose. Place a drain pan underneath the radiator drain cock.
  7. Disconnect the upper radiator hose from the radiator.
  8. Disconnect the coolant recovery reservoir hose.
  9. Remove the fan shroud bolts.
  10. Remove the fan shroud from the vehicle.
  11. Install the new fan shroud.
  12. Install the fan shroud bolts.

    13. Tighten
    Tighten the bolts to 6 N·m(53 lb in).

  13. Connect the coolant recovery reservoir hose.
  14. Connect the upper radiator hose to the radiator.
  15. Refill the cooling system.
  16. Install the new fan blade to the new fan clutch.
  17. Install the bolts and washers securing the fan blade to the fan clutch.

    18. Tighten
    Tighten the bolts in a criss-cross pattern to 21 N·m(16 lb ft).

  18. Install the new fan blade/clutch assembly to the vehicle using the J 38426 and the J 38425.

    19. Tighten
    Tighten the fan clutch nut to 145 N·m(107 lb ft).

  19. Lower the cab.

Parts Information

Part Number

Description

15094860

Clutch Asm., Fan Blade

15094861

Blade Asm., Fan

15027966

Shroud Asm., Radiator Fan

Parts are expected to be available 11-02-2001 from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

J3380

Blade, Fan -- Replace

0.7 hr

Add

To Replace Radiator Fan Shroud

0.2 hr