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Lexus SC400 Thermostat

7 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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Engine Coolant Thermostat for Toyota Camry RAV4 Ford Mitsubishi Scion Lexus 89℃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℃
4.682 Reviews
$26.99
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2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2017 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
ConditionNew
item #1013DUS4
Note
Start to Open Temperature: 89℃.
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A-Premium APTHE001 Engine Coolant Thermostat
A-Premium®Part # APTHE001
A-Premium APTHE001 Engine Coolant Thermostat
4.682 Reviews
$23.99
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2-year warranty
90 days free return
Fits 1997 - 1999 Acura CL, 2001 - 2003 Acura CL, 1991 - 1995 Acura Legend, 2001 - 2006 Acura MDX, 2007 - 2013 Acura MDX, 1991 - 2005 Acura NSX, 1997 - 2005 Acura NSX, 2013 - 2015 Acura RDX, 1996 - 2008 Acura RL, 2009 - 2012 Acura RL, 1995 - 1998 Acura TL, 1996 - 2008 Acura TL, 2007 - 2014 Acura TL, 2009 - 2014 Acura TL, 2010 - 2014 Acura TSX, 1992 - 1994 Acura Vigor, 2010 - 2013 Acura ZDX, 1995 - 2000 Chrysler Cirrus, 1996 - 1996 Chrysler Sebring, 2000 - 2000 Chrysler Sebring
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
MaterialMetal and Rubber
ConditionNew
item #1005V2X1
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A-Premium APTHE006 Engine Coolant Thermostat
A-Premium®Part # APTHE006
A-Premium APTHE006 Engine Coolant Thermostat
4.682 Reviews
$31.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2018 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1996 - 1998 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
MaterialMetal
ConditionNew
item #10156A30
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Beck/Arnley 143-0722 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0722
Beck/Arnley 143-0722 Engine Coolant Thermostat
51 Reviews
$44.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-2000 Chevrolet Prizm, 1995-1998 Eagle Talon, 1999-2005 Hyundai Sonata, 2001-2004 Hyundai Santa Fe, 2003-2006 Kia Optima, 1990-1991 Lexus ES250, 1990-1996 Lexus LS400, 1992-1995 Lexus ES300, 1992-1997 Lexus SC400, 1999-2002 Lexus ES300, 1999-2002 Lexus RX300, 2004-2004 Lexus ES330, 2007-2015 Lexus RX350, 2007-2018 Lexus ES350, 2010-2015 Lexus RX450h, 1993-1994 Mitsubishi Expo LRV, 1993-1995 Mitsubishi Expo, 1993-1998 Mitsubishi Galant, 1995-1999 Mitsubishi Eclipse, 1995-1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
QuantityOne Set
Part interchange
143-0722
item #1000XEUU
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Beck/Arnley 143-0789 Engine Coolant Thermostat
Beck/ArnleyPart # 143-0789
Beck/Arnley 143-0789 Engine Coolant Thermostat
51 Reviews
$34.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1996-1997 Lexus LX450, 1997-1997 Lexus LS400, 1998-2000 Lexus GS400, 1998-2000 Lexus LS400, 1998-2000 Lexus SC400, 1998-2007 Lexus LX470, 2001-2006 Lexus LS430, 2001-2007 Lexus GS430, 2002-2010 Lexus SC430, 2003-2009 Lexus GX470, 1993-2007 Toyota Land Cruiser, 2000-2009 Toyota Tundra, 2001-2007 Toyota Sequoia, 2003-2009 Toyota 4Runner, 2008-2009 Toyota Sequoia
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
Part interchange
143-0789
item #1000XLEH
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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
4.682 Reviews
$16.99
Edit ZIP code
2-year warranty
90 days free return
Fits 1998 - 2002 Chevrolet Prizm, 1992 - 1992 Dodge Colt, 1993 - 1996 Eagle Summit, 1995 - 1998 Eagle Talon, 1996 - 1999 Ford Taurus, 1990 - 1991 Lexus ES250, 1992 - 2003 Lexus ES300, 2004 - 2006 Lexus ES330, 2007 - 2018 Lexus ES350, 2010 - 2012 Lexus HS250h, 1990 - 1997 Lexus LS400, 1999 - 2003 Lexus RX300, 2004 - 2006 Lexus RX330, 2007 - 2015 Lexus RX350, 2006 - 2008 Lexus RX400h, 2010 - 2015 Lexus RX450h, 1992 - 1997 Lexus SC400, 1995 - 1996 Mitsubishi Eclipse, 1996 - 1998 Mitsubishi Eclipse, 1999 - 1999 Mitsubishi Eclipse
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
ConditionNew
item #1018A699
Note
Start to Open Temperature: 82℃.
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Engine Coolant Thermostat - Mahle TX 148 82
MahlePart # TX 148 82
Engine Coolant Thermostat - Mahle TX 148 82
51 Reviews
$32.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1997-2000 Lexus LS400, 1997-2000 Lexus SC400, 1998-2000 Lexus GS400, 1998-2007 Lexus LX470, 2001-2006 Lexus LS430, 2001-2007 Lexus GS430, 2002-2010 Lexus SC430, 2003-2009 Lexus GX470, 1992-2007 Toyota Land Cruiser, 2000-2009 Toyota Tundra, 2001-2007 Toyota Sequoia, 2003-2009 Toyota 4Runner, 2008-2009 Toyota Sequoia
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Lexus SC400
Item LocatedUnited States
Quantity1
Part interchange
TX 148 82, 33878, 14128, TX14882, 302-180, 90916-03100, 90916-03117, 90916-03138
item #1000XSGZ
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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

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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