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Hummer H3 Thermostat

5 items

Upgrade your vehicle's thermostat with A-Premium's high-quality options. Choose reliability and durability for a smoother ride.

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Thermostat Housing Assembly for 2006-2010 Hummer H3Thermostat Housing Assembly for 2006-2010 Hummer H3
A-Premium®Part # APTHA0029
Thermostat Housing Assembly for 2006-2010 Hummer H3
4.680 Reviews
$26.99
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2-year warranty
90 days free return
Fits Hummer H3: 2006 2007 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal
ColorNatural
item #1003D0YK
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Thermostat Housing Assembly for 2008-2010 Hummer H3
A-Premium®Part # APTHA0203
Thermostat Housing Assembly for 2008-2010 Hummer H3
4.680 Reviews
$20.99
Quantity Less than 4
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2-year warranty
90 days free return
Fits Hummer H3: 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
Installation PositionWater Pump
MaterialAluminum
item #1012ZK5U
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Engine Coolant Thermostat for 2008-2010 Hummer H3
A-Premium®Part # APTHE030
Engine Coolant Thermostat for 2008-2010 Hummer H3
4.680 Reviews
$19.99
Edit ZIP code
2-year warranty
90 days free return
Fits Hummer H3: 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NQZE
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Engine Coolant Thermostat for 2008-2010 Hummer H3
A-Premium®Part # APTHE032
Engine Coolant Thermostat for 2008-2010 Hummer H3
4.680 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits Hummer H3: 2008 2009 2010
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1012NQ6S
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Engine Coolant Thermostat - Mahle TI 222 88
MahlePart # TI 222 88
Engine Coolant Thermostat - Mahle TI 222 88
51 Reviews
$32.99
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3-year warranty
90 days free return
Fits 2004-2008 Chevrolet Colorado, 2009-2012 Chevrolet Colorado, 2009-2012 Chevrolet Colorado, 2004-2008 GMC Canyon, 2009-2012 GMC Canyon, 2009-2012 GMC Canyon, 2006-2007 Hummer H3, 2008-2010 Hummer H3, 2009-2010 Hummer H3T
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
Part interchange
TI 222 88, 34045, 48718, 538-187, TI22288, 12579956, 12622316, 12620113
item #1000XNZQ
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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.