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Engine Overheat on Vehicles Equipped with VYU Snowplow Prep Package - keywords4.8 5.3 6.0 LR4 LM7 LQ4 temp high hot light IPC DIC gauge

Subject:Engine Overheat On Vehicles Equipped With VYU Snowplow Prep Package.

Models:



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in the PI.

Condition/Concern:

Some customers may comment on high engine temperature readings when driving at highway speed with their snow plow installed on the vehicle. Temperature readings will be normal when the plow is removed.

Recommendation/Instructions:

When the vehicle is driven with the plow in the up position it will interrupt air flow into the engine compartment. When the air flow is interrupted the fan clutch may not sense the warm air coming off of the radiator. This may induce improper fan clutch operation.

  1. If the customer concern of overheating has been verified, SI diagnostics for overheating have been completed, and the overheat only occurs when driving with the snow plow installed, continue with the information found below.
  2. Verify there were no modifications made to the vehicles cooling system when the snow plow was installed. Cooling system modifications may induce overheating concerns.
  3. On K1 and K2 trucks with 4.8L, 5.3L, or 6.0L engines (equipped with the VYU snow plow prep package), replace the current fan clutch with GMSPO part number:
  4. 3.1. 22149877 (with GT4-3:73 axle)
    3.2. 15710101 (with GT5-4:10 axle)
  5. On K3 trucks with 6.0L engines (equipped with the VYU snow plow prep package), replace the current fan clutch with GMSPO part number:
  6. 22149894

NOTE: DO NOT USE ANY OTHER PART NUMBERS OR LET A PART NUMBER SUPERSESSION OCCUR, ONLY THE PART NUMBERS LISTED IN THIS PI (OR PART NUMBERS LISTED IN BULLETIN # 04-06-02-006 FOR 6.0 K2 VEHICLES) SHOULD BE USED.

Continue to make field product reports on overheating with a snowplow and document the readings below:

    • Type and size of snow plow:
    • Temperature reading off of the Tech 2 during the concern:
    • Temperature reading off dash gauge during the concern
    • Is there any DIC messages for engine coolant hot or overheated:

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

Models:

(02-05 K1 K2 K3 Chevrolet Silverado LR4 LM7 LQ9) and (02-05 K1 K2 K3 GMC Sierra LR4 LM7 LQ9)