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Ford Thermostat

95 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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A-Premium APTHA0290 Engine Coolant Thermostat Housing AssemblyA-Premium APTHA0290 Engine Coolant Thermostat Housing Assembly
A-Premium®Part # APTHA0290
A-Premium APTHA0290 Engine Coolant Thermostat Housing Assembly
4.692 Reviews
$42.99
Low stock: Only 1 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2017 Jaguar XE, 2015 - 2017 Land Rover Discovery Sport, 2013 - 2015 Jaguar XF, 2013 - 2015 Land Rover LR2, 2013 - 2013 Ford Explorer, 2012 - 2017 Land Rover Range Rover Evoque, 2012 - 2015 Ford Edge, 2012 - 2012 Ford Explorer
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Vehicle: Ford
Item LocatedUnited States
Quantity1
ColorBlack
ConditionNew
item #10156A39
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Engine Coolant Thermostat Housing Assembly for Ford F-150 Expedition E-150 Lincoln
A-Premium®Part # APTHA0120
Engine Coolant Thermostat Housing Assembly for Ford F-150 Expedition E-150 Lincoln
4.692 Reviews
$33.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2016 Ford E-450 Super Duty, 2005 - 2005 Ford E-350 Club Wagon, 2004 - 2004 Ford F-150 Heritage, 2004 - 2004 Ford F-150 Heritage, 2003 - 2019 Ford E-450 Super Duty, 2003 - 2014 Ford E-150, 2003 - 2014 Ford E-150, 2003 - 2014 Ford E-250, 2003 - 2014 Ford E-250, 2003 - 2005 Ford E-150 Club Wagon, 2003 - 2005 Ford E-150 Club Wagon, 2003 - 2005 Ford E-350 Club Wagon, 2003 - 2004 Ford E-450 Super Duty, 2003 - 2003 Ford E-350 Club Wagon, 2003 - 2003 Ford E-550 Super Duty, 2002 - 2002 Ford E-550 Econoline Super Duty, 2000 - 2005 Ford Excursion, 2000 - 2005 Ford Excursion, 2000 - 2002 Ford E-450 Econoline Super Duty, 1999 - 2019 Ford E-350 Super Duty
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #10013Y1K
Note
This item comes with Cover.
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Engine Coolant Thermostat for Ford F-150 F-250 Explorer Mustang E-150 Jeep
A-Premium®Part # APTHE035
Engine Coolant Thermostat for Ford F-150 F-250 Explorer Mustang E-150 Jeep
4.692 Reviews
$22.99
Low stock: Only 3 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2020 - 2022 Ford F-350 Super Duty, 2017 - 2019 Ford E-350 Super Duty, 2017 - 2019 Ford E-450 Super Duty, 2017 - 2019 Ford F-450 Super Duty, 2017 - 2019 Ford F-550 Super Duty, 2016 - 2019 Ford F-750, 2016 - 2016 Ford E-350 Super Duty, 2015 - 2019 Ford F-650, 2014 - 2021 Ford F-250 Super Duty, 2014 - 2018 Ford F-350 Super Duty, 2014 - 2014 Ford F-150, 2013 - 2021 Blue Bird Vision School Bus, 2012 - 2013 Ford E-350 Super Duty, 2010 - 2010 Ford Explorer Sport Trac, 2009 - 2010 Ford E-450 Super Duty, 2007 - 2010 Ford Mustang, 2007 - 2009 Ford Explorer Sport Trac, 2006 - 2016 Ford E-450 Super Duty, 2006 - 2008 Lincoln Mark LT, 2005 - 2009 Ford F-150
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DV4S
Note
Start to Open Temperature: 82℃.
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A-Premium APTHA0307 Engine Coolant Thermostat Housing Assembly
A-Premium®Part # APTHA0307
A-Premium APTHA0307 Engine Coolant Thermostat Housing Assembly
4.692 Reviews
$36.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2004 - 2006 Lincoln LS, 2003 - 2005 Ford Thunderbird, 2003 - 2003 Lincoln LS
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ColorBlack
ConditionNew
item #1005V25X
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Engine Coolant Thermostat for Toyota Camry 1988-2017 RAV4 Corolla Tacoma Highlander
A-Premium®Part # APTHE100
Engine Coolant Thermostat for Toyota Camry 1988-2017 RAV4 Corolla Tacoma Highlander
4.692 Reviews
$16.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2020 - 2020 Toyota Sienna, 2010 - 2015 Lexus RX450h, 2010 - 2012 Lexus HS250h, 2009 - 2016 Toyota Venza, 2008 - 2015 Scion xB, 2008 - 2014 Scion xD, 2007 - 2018 Lexus ES350, 2007 - 2015 Lexus RX350, 2006 - 2011 Mitsubishi Eclipse, 2006 - 2008 Lexus RX400h, 2005 - 2016 Scion tC, 2004 - 2011 Mitsubishi Galant, 2004 - 2006 Lexus ES330, 2004 - 2006 Lexus RX330, 2004 - 2006 Mitsubishi Outlander, 2004 - 2005 Mitsubishi Lancer, 2003 - 2014 Toyota Matrix, 2003 - 2010 Pontiac Vibe, 2001 - 2019 Toyota Highlander, 2001 - 2018 Toyota RAV4
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #1018A699
Note
Start to Open Temperature: 82℃.
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Engine Coolant Thermostat Housing Assembly for Ford Explorer Escape Fusion Focus
A-Premium®Part # APTHA0270
Engine Coolant Thermostat Housing Assembly for Ford Explorer Escape Fusion Focus
4.692 Reviews
$33.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2015 - 2016 Ford Fusion, 2015 - 2016 Lincoln MKC, 2014 - 2018 Ford Special Service Police Sedan, 2013 - 2017 Ford Taurus, 2013 - 2016 Ford Escape, 2013 - 2016 Lincoln MKT, 2013 - 2016 Lincoln MKZ, 2013 - 2015 Ford Explorer, 2013 - 2014 Ford Fusion, 2013 - 2013 Mazda 3 Sport, 2012 - 2013 Mazda 3, 2012 - 2012 Mazda 3 Sport, 2011 - 2018 Ford Focus, 2007 - 2015 Mazda MX-5 Miata, 2007 - 2009 Mazda 3, 2006 - 2010 Mazda 5, 2006 - 2006 Mazda MX-5 Miata, 2004 - 2011 Mazda 3, 2004 - 2006 Mazda 3
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DTUG
Note
Temperature:71℃, Alternate Temperature Option.
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Engine Coolant Thermostat Housing Assembly for Ford Escape Edge Explorer Focus
A-Premium®Part # APTHA0116
Engine Coolant Thermostat Housing Assembly for Ford Escape Edge Explorer Focus
4.692 Reviews
$36.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2016 - 2018 Ford Explorer, 2016 - 2018 Ford Focus, 2015 - 2018 Lincoln MKC, 2015 - 2018 Lincoln MKC, 2014 - 2018 Ford Special Service Police Sedan, 2013 - 2018 Ford Escape, 2013 - 2018 Ford Focus, 2013 - 2018 Ford Fusion, 2013 - 2018 Lincoln MKZ, 2013 - 2017 Ford Taurus, 2013 - 2016 Lincoln MKT, 2012 - 2018 Ford Edge, 2012 - 2015 Ford Explorer
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #10013WRE
Note
This item comes with Engine Coolant Water Outlet.
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Thermostat Housing Assembly for Ford Focus 2004-2012
A-Premium®Part # APTHA0202
Thermostat Housing Assembly for Ford Focus 2004-2012
4.692 Reviews
$50.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2004 - 2012 Ford Focus
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Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialPlastic
ConditionNew
item #1002LQZK
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A-Premium APTHE018 Engine Coolant Thermostat
A-Premium®Part # APTHE018
A-Premium APTHE018 Engine Coolant Thermostat
4.692 Reviews
$17.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1999 - 2001 Toyota Solara, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1997 - 1998 Nissan 200SX, 1996 - 2000 Toyota RAV4, 1996 - 1997 Nissan Sentra, 1995 - 1995 Nissan 200SX, 1994 - 1997 Toyota Celica, 1993 - 1997 Geo Prizm, 1993 - 1997 Toyota Corolla, 1992 - 2001 Toyota Camry, 1992 - 1999 Toyota Celica, 1992 - 1999 Toyota Paseo, 1991 - 1993 Nissan NX, 1990 - 1993 Toyota Celica, 1989 - 1999 Nissan Sentra, 1989 - 1997 Geo Prizm, 1989 - 1990 Nissan Pulsar NX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005UU8S
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A-Premium APTHE017 Engine Coolant Thermostat
A-Premium®Part # APTHE017
A-Premium APTHE017 Engine Coolant Thermostat
4.692 Reviews
$17.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2008 - 2009 Ford F-650, 2008 - 2009 Ford F-750, 1999 - 2001 Toyota Solara, 1998 - 1998 Ford F-800, 1998 - 1998 Ford F-800 LPO, 1997 - 1998 Nissan 200SX, 1996 - 2000 Toyota RAV4, 1996 - 1997 Nissan Sentra, 1995 - 1995 Nissan 200SX, 1994 - 1997 Toyota Celica, 1993 - 1997 Geo Prizm, 1993 - 1997 Toyota Corolla, 1992 - 2001 Toyota Camry, 1992 - 1999 Toyota Celica, 1992 - 1999 Toyota Paseo, 1991 - 1993 Nissan NX, 1990 - 1993 Toyota Celica, 1989 - 1999 Nissan Sentra, 1989 - 1997 Geo Prizm, 1989 - 1990 Nissan Pulsar NX
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #1005USAT
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A-Premium APTHA0305 Integrated Housing Thermostat
A-Premium®Part # APTHA0305
A-Premium APTHA0305 Integrated Housing Thermostat
4.692 Reviews
$54.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2019 Ford Escape, 2014 - 2020 Ford Fusion
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
Part interchange
34856, DS7G9K478DB, 1828684, 1890165, DS7G9K478DA
ConditionNew
item #1005UQVN
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A-Premium APTHE036 Engine Coolant Thermostat
A-Premium®Part # APTHE036
A-Premium APTHE036 Engine Coolant Thermostat
4.692 Reviews
$25.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2020 - 2022 Ford F-350 Super Duty, 2017 - 2019 Ford E-350 Super Duty, 2017 - 2019 Ford E-450 Super Duty, 2017 - 2019 Ford F-450 Super Duty, 2017 - 2019 Ford F-550 Super Duty, 2016 - 2019 Ford F-750, 2015 - 2019 Ford F-650, 2014 - 2021 Ford F-250 Super Duty, 2014 - 2018 Ford F-350 Super Duty, 2014 - 2014 Ford F-150, 2013 - 2021 Blue Bird Vision School Bus, 2010 - 2010 Ford Explorer Sport Trac, 2009 - 2010 Ford E-450 Super Duty, 2007 - 2010 Ford Mustang, 2007 - 2009 Ford Explorer Sport Trac, 2006 - 2016 Ford E-450 Super Duty, 2006 - 2008 Lincoln Mark LT, 2005 - 2009 Ford F-150, 2005 - 2006 Mercury Monterey, 2004 - 2010 Ford F-150
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal, Rubber
ConditionNew
item #1005V4XL
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Engine Coolant Thermostat for Toyota Camry RAV4 Ford Mitsubishi Scion Lexus 89℃
A-Premium®Part # APTHE071
Engine Coolant Thermostat for Toyota Camry RAV4 Ford Mitsubishi Scion Lexus 89℃
4.692 Reviews
$26.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2017 Toyota Highlander, 2016 - 2017 Toyota RAV4, 2012 - 2017 Toyota Camry, 2012 - 2012 Toyota RAV4, 2011 - 2016 Scion tC, 2011 - 2013 Toyota Sienna, 2010 - 2015 Lexus RX450h, 2010 - 2012 Lexus HS250h, 2010 - 2011 Toyota Camry, 2009 - 2016 Toyota Highlander, 2009 - 2016 Toyota Venza, 2009 - 2016 Toyota Venza, 2009 - 2015 Toyota RAV4, 2009 - 2013 Toyota Matrix, 2009 - 2012 Toyota Corolla, 2009 - 2010 Pontiac Vibe, 2008 - 2016 Toyota Highlander, 2008 - 2015 Scion xB, 2008 - 2014 Scion xD, 2007 - 2017 Lexus ES350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DUS4
Note
Start to Open Temperature: 89℃.
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Thermostat Housing Assembly for Ford Fusion 2014-2020 Escape 2017-2019
A-Premium®Part # APTHA0237
Thermostat Housing Assembly for Ford Fusion 2014-2020 Escape 2017-2019
4.692 Reviews
$39.99
Low stock: Only 2 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2019 Ford Escape, 2014 - 2020 Ford Fusion
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialAluminum
ConditionNew
item #10027T8R
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A-Premium APTHE016 Engine Coolant Thermostat
A-Premium®Part # APTHE016
A-Premium APTHE016 Engine Coolant Thermostat
4.692 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2020 Lincoln Continental, 2014 - 2019 Ford Police Interceptor Utility, 2013 - 2019 Ford Police Interceptor Sedan, 2013 - 2019 Ford Police Interceptor Sedan, 2013 - 2019 Ford Police Interceptor Utility, 2013 - 2016 Lincoln MKZ, 2011 - 2019 Ford Explorer, 2011 - 2018 Lincoln MKX, 2011 - 2014 Ford Edge, 2010 - 2019 Lincoln MKT, 2010 - 2019 Lincoln MKT, 2010 - 2016 Lincoln MKS, 2010 - 2012 Ford Fusion, 2009 - 2019 Ford Flex, 2009 - 2016 Lincoln MKS, 2008 - 2019 Ford Taurus, 2008 - 2009 Ford Taurus X, 2008 - 2009 Mercury Sable, 2007 - 2018 Ford Edge, 2007 - 2012 Lincoln MKZ
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2Q9
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A-Premium APTHE023 Engine Coolant Thermostat
A-Premium®Part # APTHE023
A-Premium APTHE023 Engine Coolant Thermostat
4.692 Reviews
$26.99
Low stock: Only 5 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2019 - 2019 Mazda CX-5, 2018 - 2018 Mazda 3, 2018 - 2018 Mazda 3, 2018 - 2018 Mazda 3 Sport, 2018 - 2018 Mazda 3 Sport, 2018 - 2018 Mazda 6, 2017 - 2017 Mazda 3, 2017 - 2017 Mazda 3, 2014 - 2017 Mazda 6, 2014 - 2016 Mazda 3, 2014 - 2016 Mazda 3 Sport, 2014 - 2016 Mazda 3 Sport, 2014 - 2016 Mazda CX-5, 2013 - 2016 Mazda CX-5, 2012 - 2016 Mazda 3, 2011 - 2014 Mazda 2, 2011 - 2011 Mazda 3 Sport, 2004 - 2004 Chevrolet Tracker, 2002 - 2003 Mazda Protege5, 2002 - 2002 Mazda Protege
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V5HT
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Engine Coolant Thermostat for Ford F-150 Explorer Mustang E-250 Econoline
A-Premium®Part # APTHA350PG
Engine Coolant Thermostat for Ford F-150 Explorer Mustang E-250 Econoline
4.692 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1995 - 1995 Ford E-350 Econoline, 1995 - 1995 Ford E-350 Econoline Club Wagon, 1994 - 1995 Ford F-250, 1994 - 1995 Ford F-350, 1994 - 1994 Ford Aerostar, 1994 - 1994 Ford Aerostar, 1994 - 1994 Ford Aspire, 1994 - 1994 Ford Bronco, 1994 - 1994 Ford Bronco, 1994 - 1994 Ford Crown Victoria, 1994 - 1994 Ford E-150 Econoline, 1994 - 1994 Ford E-150 Econoline, 1994 - 1994 Ford E-150 Econoline, 1994 - 1994 Ford E-150 Econoline Club Wagon, 1994 - 1994 Ford E-150 Econoline Club Wagon, 1994 - 1994 Ford E-150 Econoline Club Wagon, 1994 - 1994 Ford E-250 Econoline, 1994 - 1994 Ford E-250 Econoline, 1994 - 1994 Ford E-350 Econoline, 1994 - 1994 Ford E-350 Econoline
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
ConditionNew
item #1018A6WH
Note
Start to Open Temperature: 88℃.
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Thermostat Housing Assembly for Lincoln LS 2000-2003 Ford Thunderbird
A-Premium®Part # APTHA0178
Thermostat Housing Assembly for Lincoln LS 2000-2003 Ford Thunderbird
4.692 Reviews
$48.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2003 - 2003 Lincoln LS, 2002 - 2002 Ford Thunderbird, 2000 - 2002 Lincoln LS
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
ColorBlack
ConditionNew
item #10027LU3
Note
This item comes with housing and o-ring.
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Engine Coolant Thermostat Housing Assembly for Ford Focus Lincoln Mazda Mercury
A-Premium®Part # APTHA0082
Engine Coolant Thermostat Housing Assembly for Ford Focus Lincoln Mazda Mercury
4.692 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2014 - 2022 Ford Transit Connect, 2012 - 2017 Mazda 5, 2011 - 2012 Lincoln MKZ, 2010 - 2020 Ford Fusion, 2010 - 2013 Mazda 3, 2010 - 2013 Mazda 3 Sport, 2010 - 2012 Mazda CX-7, 2010 - 2011 Mercury Milan, 2009 - 2019 Ford Escape, 2009 - 2013 Mazda 6, 2009 - 2011 Mazda Tribute, 2009 - 2011 Mercury Mariner, 2008 - 2008 Mazda Tribute, 2007 - 2013 Mazda 3, 2007 - 2012 Mazda CX-7, 2007 - 2011 Ford Ranger, 2006 - 2010 Ford Fusion, 2006 - 2009 Mercury Milan, 2006 - 2008 Mercury Mariner, 2006 - 2006 Mazda MX-5 Miata
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
ColorBlack
ConditionNew
item #1005DVVG
Note
Engine Coolant Thermostat Housing Assembly -- Cover, Includes Thermostat.
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A-Premium APTHE052 Engine Coolant Thermostat
A-Premium®Part # APTHE052
A-Premium APTHE052 Engine Coolant Thermostat
4.692 Reviews
$17.99
Low stock: Only 4 left
Edit ZIP code
2-year warranty
90 days free return
Fits 2013 - 2019 Ford F-59 Commercial Stripped Chassis, 2011 - 2019 Ford F-53 Motorhome Chassis, 2006 - 2009 Ford F-53 Motorhome Chassis, 2005 - 2005 Ford E-350 Club Wagon, 2003 - 2019 Ford E-450 Super Duty, 2003 - 2003 Ford E-350 Club Wagon, 2003 - 2003 Ford E-550 Super Duty, 2002 - 2002 Ford E-550 Econoline Super Duty, 2000 - 2005 Ford Excursion, 1999 - 2019 Ford E-350 Super Duty, 1999 - 2016 Ford F-450 Super Duty, 1999 - 2016 Ford F-550 Super Duty, 1999 - 2010 Ford F-250 Super Duty, 1999 - 2010 Ford F-350 Super Duty, 1999 - 2004 Ford F-53 Motorhome Chassis, 1999 - 2002 Ford E-450 Econoline Super Duty, 1997 - 2002 Ford E-350 Econoline Club Wagon, 1997 - 1999 Ford Econoline Super Duty, 1997 - 1998 Ford E-350 Econoline
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Ford
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #10156CCR
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Page 1 of 5

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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