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Western Star Thermostat

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Engine Coolant Thermostat for 2010-2018 Western Star 4900SAEngine Coolant Thermostat for 2010-2018 Western Star 4900SA
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 2010-2018 Western Star 4900SA
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900SA: 2010 2011 2012 2013 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GRCQ
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Diesel Thermostat with Seal for 2016-2022 Western Star 5700XE
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2016-2022 Western Star 5700XE
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 5700XE: 2016 2017 2018 2019 2020 2021 2022
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188P35
Note
Start to Open Temperature: 87℃.
Show less
Engine Coolant Thermostat for 2015-2016 Western Star 6900XD
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 2015-2016 Western Star 6900XD
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 6900XD: 2015 2016
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GS6U
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Engine Coolant Thermostat for 1998-2001 Western Star 5800
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 1998-2001 Western Star 5800
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 5800: 1998 1999 2000 2001
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GR58
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Engine Coolant Thermostat for 2000-2001 Western Star 4900
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 2000-2001 Western Star 4900
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900: 2000 2001
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GQTG
Show less
Diesel Thermostat with Seal for 2009-2023 Western Star 4900FA
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2009-2023 Western Star 4900FA
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900FA: 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188L0P
Note
Start to Open Temperature: 87℃.
Show less
Engine Coolant Thermostat for 2011-2018 Western Star 4900FA
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 2011-2018 Western Star 4900FA
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900FA: 2011 2012 2013 2014 2015 2016 2017 2018
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GR06
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Engine Coolant Thermostat for 1999-2000 Western Star 4800
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 1999-2000 Western Star 4800
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4800: 1999 2000
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GUC6
Show less
Engine Coolant Thermostat for 2003 2011-2020 Western Star 4900EX
A-Premium®Part # APTHE079
Engine Coolant Thermostat for 2003 2011-2020 Western Star 4900EX
4.653 Reviews
$29.99
Quantity Less than 4
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900EX: 2003 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
ConditionNew
item #1014GU58
Show less
Diesel Thermostat with Seal for 2013-2020 Western Star 4700SB
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2013-2020 Western Star 4700SB
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4700SB: 2013 2014 2015 2016 2017 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188KT2
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2009-2022 Western Star 4900SA
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2009-2022 Western Star 4900SA
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900SA: 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188N9Q
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2013-2020 Western Star 4700SF
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2013-2020 Western Star 4700SF
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4700SF: 2013 2014 2015 2016 2017 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188NWY
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2013-2020 Western Star 4800SF
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2013-2020 Western Star 4800SF
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4800SF: 2013 2014 2015 2016 2017 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188HSZ
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2009-2022 Western Star 4900EX
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2009-2022 Western Star 4900EX
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4900EX: 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188NRC
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2012-2020 Western Star 4800SB
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2012-2020 Western Star 4800SB
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 4800SB: 2012 2013 2014 2015 2016 2017 2018 2019 2020
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188NNY
Note
Start to Open Temperature: 87℃.
Show less
Diesel Thermostat with Seal for 2011-2012 2019 2022 Western Star 6900XD
A-Premium®Part # APTHA0343
Diesel Thermostat with Seal for 2011-2012 2019 2022 Western Star 6900XD
4.653 Reviews
$107.99
Edit ZIP code
2-year warranty
90 days free return
Fits Western Star 6900XD: 2011 2012 2019 2022
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Western Star
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
Part interchange
4712002915, 4712003615, 4712006215, 4712007515, A4712002915, A4712003615, A4712006215, A4712007515
ConditionNew
item #10188NL3
Note
Start to Open Temperature: 87℃.
Show less

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.