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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 Chevrolet Silverado 1500 GMC Canyon Sierra 1500Thermostat Housing Assembly for Chevrolet Silverado 1500 GMC Canyon Sierra 1500
A-Premium®Part # APTHA0203
Thermostat Housing Assembly for Chevrolet Silverado 1500 GMC Canyon Sierra 1500
4.682 Reviews
$20.99
Low stock: Only 4 left
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2-year warranty
90 days free return
Fits 2007 - 2007 Buick Rainier, 2009 - 2013 Cadillac Escalade, 2007 - 2014 Cadillac Escalade, 2021 - 2022 Cadillac Escalade, 2007 - 2014 Cadillac Escalade ESV, 2021 - 2022 Cadillac Escalade ESV, 2007 - 2013 Cadillac Escalade EXT, 2007 - 2013 Chevrolet Avalanche, 2007 - 2009 Chevrolet Avalanche, 2009 - 2012 Chevrolet Colorado, 2020 - 2022 Chevrolet Corvette, 2007 - 2014 Chevrolet Express 1500, 2018 - 2022 Chevrolet Express 2500, 2007 - 2017 Chevrolet Express 2500, 2007 - 2020 Chevrolet Express 2500, 2021 - 2022 Chevrolet Express 2500, 2018 - 2022 Chevrolet Express 3500, 2007 - 2017 Chevrolet Express 3500, 2007 - 2008 Chevrolet Express 3500, 2007 - 2020 Chevrolet Express 3500
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Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
Installation PositionWater Pump
MaterialAluminum
item #1000W523
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A-Premium APTHE030 Engine Coolant Thermostat
A-Premium®Part # APTHE030
A-Premium APTHE030 Engine Coolant Thermostat
4.682 Reviews
$19.99
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2-year warranty
90 days free return
Fits 2007 - 2007 Buick Rainier, 2019 - 2020 Cadillac CT6, 2009 - 2014 Cadillac CTS, 2009 - 2013 Cadillac Escalade, 2007 - 2014 Cadillac Escalade, 2021 - 2023 Cadillac Escalade, 2023 - 2023 Cadillac Escalade ESV, 2007 - 2009 Cadillac Escalade ESV, 2011 - 2014 Cadillac Escalade ESV, 2021 - 2023 Cadillac Escalade ESV, 2007 - 2008 Cadillac Escalade EXT, 2009 - 2013 Cadillac Escalade EXT, 2007 - 2007 GMC C8500 Topkick, 2009 - 2012 GMC Canyon, 2007 - 2009 GMC Envoy, 2007 - 2014 GMC Savana 1500, 2007 - 2017 GMC Savana 2500, 2008 - 2020 GMC Savana 2500, 2007 - 2010 GMC Savana 3500, 2012 - 2017 GMC Savana 3500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V1U2
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A-Premium APTHE032 Engine Coolant Thermostat
A-Premium®Part # APTHE032
A-Premium APTHE032 Engine Coolant Thermostat
4.682 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2007 - 2007 Buick Rainier, 2009 - 2014 Cadillac CTS, 2007 - 2014 Cadillac Escalade, 2009 - 2013 Cadillac Escalade, 2021 - 2023 Cadillac Escalade, 2007 - 2014 Cadillac Escalade ESV, 2021 - 2023 Cadillac Escalade ESV, 2007 - 2013 Cadillac Escalade EXT, 2007 - 2007 GMC C8500 Topkick, 2009 - 2012 GMC Canyon, 2007 - 2009 GMC Envoy, 2007 - 2014 GMC Savana 1500, 2007 - 2017 GMC Savana 2500, 2007 - 2020 GMC Savana 2500, 2018 - 2021 GMC Savana 2500, 2021 - 2022 GMC Savana 2500, 2007 - 2017 GMC Savana 3500, 2007 - 2020 GMC Savana 3500, 2018 - 2021 GMC Savana 3500, 2021 - 2022 GMC Savana 3500
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V0PY
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Thermostat Housing Assembly for Chevrolet Colorado GMC Canyon 04-12 Hummer H3
A-Premium®Part # APTHA0029
Thermostat Housing Assembly for Chevrolet Colorado GMC Canyon 04-12 Hummer H3
4.682 Reviews
$26.99
Low stock: Only 4 left
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2-year warranty
90 days free return
Fits 2004 - 2006 Chevrolet Colorado, 2007 - 2012 Chevrolet Colorado, 2004 - 2006 Chevrolet Colorado, 2007 - 2012 Chevrolet Colorado, 2004 - 2006 GMC Canyon, 2007 - 2012 GMC Canyon, 2004 - 2006 GMC Canyon, 2007 - 2012 GMC Canyon, 2006 - 2006 Hummer H3, 2007 - 2010 Hummer H3, 2009 - 2010 Hummer H3T
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Hummer H3
Item LocatedUnited States
Quantity1
MaterialMetal
ColorNatural
item #1003CVUK
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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
Edit ZIP code
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.

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Jul 29, 2026