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Thermostat Assembly Replace 21200-31U1B Compatible with Nissan 4.0L Infiniti 3.5L - 2003-2006 350Z G35, 2005-2019 Frontier, 2005-2012 Pathfinder, 2005-2015 Xterra, 2012-2021 NV1500 NV2500 NV3500, More

  • Based on 26 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Friday, Aug 29
Order within 1 hour and 45 minutes
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Features

  • REPLACEMENT ENGINE THERMOSTAT : An engine's thermostat regulates the temperature of the engine by controlling coolant flow. Symptoms of a failing thermostat: high temperature reading and engine overheating; low temperature reading and underheated engine; temperature changing erratically; coolant leaks around thermostat housing or under vehicle. You can find your car's thermostat by starting at the upper radiator hose and following it to where it enters the top of the engine.
  • COMPATIBLE WITH NISSAN 3.5L 4.0L V6 VEHICLES : 2003-2006 350Z 3.5L | 2005-2019 Frontier | 2012-2021 NV1500 | 2012-2021 NV2500 | 2012-2021 NV3500 | 2005-2012 Pathfinder | 2005-2015 Xterra thermostat.
  • REPLACES PART # : 21200-31U1B, 2120031U1B thermostat. The thermostat can compatible with Infiniti 3.5L V6 : 2004 FX35 | 2003-2007 G35 | 2006-2008 M35. Please check the description to confirm the compatibility before purchase. Thank you!
  • OE FIT, FORM, FUNCTION : Professional, high quality OE style and meet or exceed all original equipment performance replacement thermostat. Constructed with premium materials. Stainless steel mounting flange designed to properly fit and seat the thermostat in outlet casting, resulting in better performance. Channel constructed stainless steel spring frame for extra strength.
  • FRIENDLY NOTE : If the thermostat fails on your vehicle, simply contact us for a replacement. Also if you have any other questions on our this thermostat, please contact us at the first time. This is NOT a genuine part, it's a aftermarket replacement part manufactured by Allmotorparts.

Description

An engine's thermostat regulates the temperature of the engine by controlling coolant flow, its job is to block the flow of coolant to the radiator until the engine has warmed up. Symptoms of a bad or failing thermostat: high temperature reading and engine overheating; low temperature reading and underheated engine; temperature changing erratically; coolant leaks around thermostat housing or under vehicle. Compatible with Nissan 3.5L 4.0L V6 Vehicles: 2003-2006 350Z 3.5L 2005-2019 Frontier 2012-2021 NV1500 2012-2021 NV2500 2012-2021 NV3500 2005-2012 Pathfinder 2005-2015 Xterra Compatible with Infiniti 3.5L V6 Vehicles: 2004 FX35 2003-2007 G35 2006-2008 M35 Replaces Part : 21200-31U1B, 2120031U1B thermostat with gasket. NOTE: This is NOT a genuine part, it's a aftermarket replacement part manufactured by Allmotorparts. NOTE: To ensure accurate fitment, please confirm your vehicle information in the above compatibility section and the description.

Manufacturer: ‎Allmotorparts


Brand: ‎Allmotorparts


Item Weight: ‎10.2 ounces


Package Dimensions: ‎4.96 x 4.21 x 3.7 inches


Manufacturer Part Number: ‎AMP349


Date First Available: April 22, 2017


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Aug 29

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Product looks good material
Works good no leaks
Reviewed in the United States on April 17, 2025 by emilio guzman

  • Works!
Great quality for the price. it worked as it should ! No more overheating
Reviewed in the United States on March 7, 2025 by i. ortega

  • Ok
Ok
Reviewed in the United States on July 10, 2025 by EidonFreeman

  • Made all the differnce
I needed this right away and they were spot on. Excellent quality.
Reviewed in the United States on October 14, 2024 by Darrell942 Darrell942

  • 👍
Working well.
Reviewed in the United States on February 10, 2025 by Judy Reburn

  • Perfectamente en que nesesitaba
Ala perfección
Reviewed in the United States on March 11, 2025 by Jorge

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