1996 Chevy Truck overheating

1996 CHEVROLET TRUCK
251,000 MILES • 6 CYL • 2WD • AUTOMATIC
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PWILSO18
  • MEMBER
  • 1 POST
Not losing antifeeze, waterpump not leaking, and the fan clutch is working fine, but after I drive my chevy c-1500 truck for more than 20 minutes it wants to overheat. However, when I turn on the heater, the temp goes back to normal. I have put on new hoses, new thermostat and radiator cap, still does it. Had it tested, no head gasket leaks.
Jun 5, 2010 at 2:47 PM
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CARADIODOC
  • CAR REPAIR CONTRIBUTOR
  • 34,309 POSTS
Hi pwilso18. Welcome to the forum. If the overheating does not occur at highway speeds, the problem is related to insufficient air flow through the radiator. Either it is clogged with a bug collection or the fan clutch is not working. A missing shroud around the back of the radiator will also cause overheating at low speeds.

If the overheating DOES occur at highway speeds, look at the cooling fins of the radiator. If they are corroded away or crumble when you touch them, they are no longer transferring heat to the air. The typical symptom is the one you already noticed where turning on the heater works as a small radiator. This is more common in the states where they melt an ounce of snow with a pound of road salt.

caradiodoc
Jun 5, 2010 at 3:17 PM
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