ENGINE OVERHEATS -POSSIBLE INCORRECT THERMOSTAT INSTALLED. GMC Truck S15 Pickup - 4WD 1986

For 1990-2009 cars

# ENGINE OVERHEATS -POSSIBLE INCORRECT THERMOSTAT INSTALLED

#### VEHICLES AFFECTED: 1986-87 6.0/7.0/7.4L ENGINES (ENGINE CODES 7.4L LIGHT DUTY N AND W, 6.0/7.0L MED. DUTY B AND E

There have been reported cases of 6.0/7.0/7.4L engine overheats that were caused by having the wrong style thermostat installed. When investigating for cause of engine overheat, check for proper style of thermostat (See Illustration).

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