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Triumph Thermostat

6 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 APTHE004 Engine Coolant ThermostatA-Premium APTHE004 Engine Coolant Thermostat
A-Premium®Part # APTHE004
A-Premium APTHE004 Engine Coolant Thermostat
4.795 Reviews
$31.99
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2013 - 2021 Blue Bird Vision School Bus, 2006 - 2008 Lincoln Mark LT, 2006 - 2008 Nissan Frontier, 2005 - 2006 Mercury Monterey, 2005 - 2006 Volkswagen Jetta, 2002 - 2010 Mercury Mountaineer, 2002 - 2002 Lincoln Blackwood, 2000 - 2004 Nissan Xterra, 1999 - 1999 INFINITI G20, 1998 - 2014 Lincoln Navigator, 1998 - 2001 Nissan Sentra, 1996 - 1998 Nissan 200SX, 1995 - 1997 Nissan Pickup, 1995 - 1995 Toyota Pickup, 1994 - 1997 Mercury Cougar, 1994 - 1995 Saab 900, 1993 - 2001 Nissan Altima, 1992 - 2011 Mercury Grand Marquis, 1992 - 1992 Isuzu Stylus, 1991 - 2011 Lincoln Town Car
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Vehicle: Triumph
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2C8
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A-Premium APTHE003 Engine Coolant Thermostat
A-Premium®Part # APTHE003
A-Premium APTHE003 Engine Coolant Thermostat
4.795 Reviews
$20.99
Low stock: Only 3 left
Enter ZIP codeFree standard shipping
2-year warranty
90 days free return
Fits 2013 - 2021 Blue Bird Vision School Bus, 2006 - 2008 Lincoln Mark LT, 2005 - 2006 Mercury Monterey, 2005 - 2006 Volkswagen Jetta, 2002 - 2010 Mercury Mountaineer, 2002 - 2002 Lincoln Blackwood, 1998 - 2014 Lincoln Navigator, 1995 - 1995 Toyota Pickup, 1994 - 1997 Mercury Cougar, 1994 - 1995 Saab 900, 1992 - 2011 Mercury Grand Marquis, 1992 - 1992 Isuzu Stylus, 1992 - 1992 Saab 9000, 1991 - 2011 Lincoln Town Car, 1991 - 1993 Saab 900, 1990 - 1995 Saab 9000, 1990 - 1991 Peugeot 405, 1989 - 1989 Peugeot 405, 1987 - 1988 Mazda RX-7, 1986 - 1990 Saab 9000
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Vehicle: Triumph
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2KW
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Beck/Arnley 143-0149 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0149
Beck/Arnley 143-0149 Engine Coolant Thermostat
52 Reviews
$19.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1998-2005 Volkswagen Beetle, 1998-2005 Volkswagen Passat, 1997-2002 Audi A4, 1988-1989 Eagle Premier, 1983-1984 Nissan Pulsar NX, 1983-1983 Nissan Sentra, 1980-1981 Triumph TR8, 1980-1980 Rover 3500, 1977-1980 MG MGB, 1975-1979 MG Midget, 1975-1978 Ford Pinto, 1975-1976 Triumph TR6, 1975-1975 Opel 1900, 1975-1975 Opel Manta, 1974-1974 Opel 1900, 1974-1974 Opel Manta, 1974-1974 Triumph TR6, 1973-1980 Triumph Spitfire, 1973-1976 MG MGB, 1973-1975 Austin Marina
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Triumph
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0149
item #1000XG3Z
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Beck/Arnley 143-0701 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0701
Beck/Arnley 143-0701 Engine Coolant Thermostat
52 Reviews
$21.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2004-2006 Volvo S80, 2004-2004 Volvo S40, 2003-2003 Volvo S40, 2002-2002 Volvo V70, 2000-2004 Volvo V40, 2000-2002 Volvo S40, 2000-2002 Volvo S40, 1998-2004 Volvo C70, 1998-2001 Volvo V70, 1998-2000 Volvo S70, 1997-1998 Volvo S90, 1997-1998 Volvo V90, 1993-1997 Volvo 850, 1992-1997 Volvo 960, 1986-1987 Isuzu Trooper, 1986-1986 Saab 900, 1985-1988 Saab 900, 1985-1985 Saab 900, 1981-1987 Isuzu Pickup, 1981-1984 Isuzu I-Mark
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Triumph
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0701
item #1000XDHN
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Beck/Arnley 143-0702 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0702
Beck/Arnley 143-0702 Engine Coolant Thermostat
52 Reviews
$21.99
Low stock: Only 1 left
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 2004-2006 Volvo S80, 2004-2004 Volvo S40, 2003-2003 Volvo S40, 2002-2002 Volvo V70, 2000-2004 Volvo V40, 2000-2002 Volvo S40, 2000-2002 Volvo S40, 1998-2004 Volvo C70, 1998-2001 Volvo V70, 1998-2000 Volvo S70, 1997-1998 Volvo S90, 1997-1998 Volvo V90, 1993-1997 Volvo 850, 1992-1997 Volvo 960, 1986-1987 Isuzu Trooper, 1986-1986 Saab 900, 1985-1988 Saab 900, 1985-1985 Saab 900, 1981-1987 Isuzu Pickup, 1981-1984 Isuzu I-Mark
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Triumph
Item LocatedUnited States
Quantity1
Part interchange
143-0702
item #1000XG05
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Beck/Arnley 143-0156 Engine Coolant ThermostatSOLD OUT
Beck/ArnleyPart # 143-0156
Beck/Arnley 143-0156 Engine Coolant Thermostat
52 Reviews
$15.99
Enter ZIP codeFree standard shipping
3-year warranty
90 days free return
Fits 1988-1989 Eagle Premier, 1983-1984 Nissan Pulsar NX, 1983-1983 Nissan Sentra, 1980-1981 Triumph TR8, 1980-1980 Rover 3500, 1977-1980 MG MGB, 1975-1979 MG Midget, 1975-1978 Ford Pinto, 1975-1976 Triumph TR6, 1975-1975 Opel 1900, 1975-1975 Opel Manta, 1974-1974 Opel 1900, 1974-1974 Opel Manta, 1974-1974 Triumph TR6, 1973-1980 Triumph Spitfire, 1973-1976 MG MGB, 1973-1975 Austin Marina, 1973-1974 Opel Manta, 1973-1974 Saab 99, 1971-1974 Opel 1900
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Triumph
Item LocatedUnited States
Quantity1
Part interchange
143-0156
item #1000XG9H
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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.

Related Blogs

Why Does Coolant Boil After You Turn the Engine Off?

Learn why coolant boils or bubbles after you turn the engine off, how heat soak affects the cooling system, and how to diagnose leaks, trapped air, cap, thermostat, fan, water pump, or head gasket problems.

Jul 29, 2026