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Thermostat

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Engine Coolant Thermostat
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Engine Coolant Thermostat for Chevrolet C2500 GMC C3500HD Buick Century Pontiac
$20.99
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2-year warranty
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Vehicle: 1999 GMC K3500
Item LocatedUnited States
Quantity1
Part interchange
267-195, 33329, 26795, 10226109, 12559269, 12559575, 24507563, 10115785, 
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Engine Coolant Thermostat
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Engine Coolant Thermostat for Chevrolet Silverado 1500 Tahoe Express 2500 K3500
$14.99
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Vehicle: 1999 GMC K3500
Item LocatedUnited States
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MaterialPlastic
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12257859, 12563335, 12597583, 12632948, 34769
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Engine Coolant Thermostat
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Engine Coolant Thermostat for GMC S15 Isuzu Oldsmobile Pontiac Subaru Suzuki 91℃
$20.99
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2-year warranty
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Vehicle: 1999 GMC K3500
Item LocatedUnited States
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Part interchange
203-195, 20395, 10078980, 10182377, 10207375, 24506986, 24577299, 3037747, 
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ConditionNew
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Engine Coolant Thermostat - Mahle TX 52 92
Mahle
Engine Coolant Thermostat - Mahle TX 52 92
$25.99
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3-year warranty
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Vehicle: 1999 GMC K3500
Item LocatedUnited States
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Part interchange
TX 52 92, 34769, 131-151, 14119, TX5292, 265-195, 12 597 583, 1.436.92
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What is an engine thermostat?

 While all engines can become too hot, if your thermostat isn't working correctly, your engine's well-being is at serious risk. The engine thermostat, often simply referred to as a thermostat, regulates the engine's operating temperature within an optimal range (typically around 195 to 220 degrees Fahrenheit).

How does a car thermostat work?

As a temperature-sensitive valve within the cooling system, a car thermostat responds to changes in coolant temperature. Understanding how it works by the following breakdown steps:

  • Closed position (cold start)

Initially closed to help the engine warm up quickly.

  • Heating up

The engine generates heat during operation.

  • Opening the thermostat

A temperature-sensitive element (usually wax) causes the thermostat to open gradually.

  • Coolant flow

When open, coolant flows from the engine to the radiator.

  • Maintaining optimal temperature

Adjusts coolant flow to maintain the ideal engine temperature.

  • Temperature regulation

Continuously adjusts to prevent overheating and ensure efficient operation.

Signs of a bad thermostat

  1. Overheating: The engine becomes excessively hot due to a stuck-closed thermostat.
  2. Low or fluctuating temperature: A thermostat stuck open results in a cooler engine, affecting fuel efficiency and heating.
  3. Temperature warning light: Illuminates to indicate engine overheating due to a faulty thermostat.
  4. Poor fuel efficiency: Stuck-open thermostat reduces fuel efficiency as the engine operates less efficiently at lower temperatures.
  5. Inadequate cabin heating: Insufficient cabin heating in cold weather with a thermostat that's stuck open.
  6. Coolant leaks: Gasket or sealing issues can lead to coolant leaks.
  7. Rapid temperature fluctuations: The gauge shows rapid swings between hot and cold.
  8. Engine running hot at idle: Higher engine temperature during idle or in traffic due to restricted coolant flow.
  9. Slow or inconsistent warm-up: Longer-than-normal warm-up times, even in moderate weather.
  10. Inconsistent heater operation: This affects the performance of the vehicle's heater, causing inconsistent or inadequate heating in cold weather.