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2018 Lexus GS450h Thermostat

3 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 Housing Assembly for Lexus GS350 GS450h IS250 IS300Engine Coolant Thermostat Housing Assembly for Lexus GS350 GS450h IS250 IS300
A-Premium®Part # APTHA0093
Engine Coolant Thermostat Housing Assembly for Lexus GS350 GS450h IS250 IS300
4.687 Reviews
$25.99
Low stock: Only 3 left
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2-year warranty
90 days free return
Fits 2007 - 2011 Lexus GS350, 2013 - 2015 Lexus GS350, 2007 - 2011 Lexus GS450h, 2013 - 2018 Lexus GS450h, 2006 - 2015 Lexus IS250, 2016 - 2017 Lexus IS300, 2006 - 2017 Lexus IS350, 2016 - 2017 Lexus RC300, 2015 - 2017 Lexus RC350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2018 Lexus GS450h
Item LocatedUnited States
Quantity1
MaterialPlastic
ConditionNew
item #1005EY6L
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ÜRO Parts TY0717617 Engine Coolant Thermostat / Water Inlet Assembly
ÜRO PartsPart # TY0717617
ÜRO Parts TY0717617 Engine Coolant Thermostat / Water Inlet Assembly
52 Reviews
$33.99
Low stock: Only 2 left
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3-year warranty
90 days free return
Fits 2006-2006 Lexus GS300, 2006-2015 Lexus IS250, 2006-2018 Lexus IS350, 2007-2011 Lexus GS350, 2007-2011 Lexus GS450h, 2013-2015 Lexus GS350, 2013-2018 Lexus GS450h, 2015-2018 Lexus RC350, 2016-2017 Lexus IS300, 2016-2017 Lexus RC300, 2018-2018 Lexus IS300
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2018 Lexus GS450h
Item LocatedUnited States
Quantity1
ColorBlack
Part interchange
TY0717617, 16031-31020, THT-004, 1430879, 902-5137, 86112, 34711, TI31082, 
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item #1000ZSD6
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Beck/Arnley 143-0879 Engine Coolant Thermostat Housing Assembly
Beck/ArnleyPart # 143-0879
Beck/Arnley 143-0879 Engine Coolant Thermostat Housing Assembly
51 Reviews
$59.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2006-2006 Lexus GS300, 2006-2015 Lexus IS250, 2006-2018 Lexus IS350, 2007-2011 Lexus GS350, 2007-2011 Lexus GS450h, 2013-2015 Lexus GS350, 2013-2018 Lexus GS450h, 2015-2017 Lexus RC350, 2016-2017 Lexus IS300, 2016-2017 Lexus RC300, 2018-2018 Lexus IS300, 2018-2018 Lexus RC300, 2018-2018 Lexus RC350
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: 2018 Lexus GS450h
Item LocatedUnited States
Quantity1
Part interchange
143-0879
item #1000X7SL
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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