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Cummins 3800884

Cummins 3800884 Thermostat for B/QSB 3.3L engines


B/QSB 3.3L Cummins 3800884 Replacement Thermostat

PLEASE ENTER YOUR ENGINE SERIAL NUMBER - ESN SO WE CAN VERIFY THE CORRECT THERMOSTAT FOR YOUR ENGINE. CUMMINS PARTS ARE NON-REFUNDABLE. You must enter your EIN to purchase this part.  If you are using the part number from the actual part in hand, you may enter it in the EIN field to verify this is the part you want. 

This Cummins 3800884 Thermostat is an OEM replacement Thermostat for Cummins B/QSB 3.3L Diesel engines. This thermostat is the stock replacement part needed for a leak-proof change for the correct engine operating temperatures. This Cummins Thermostat contains the following required Original Equipment Manufacturer parts:

  • Thermostat

This Cummins 3800884 Replacement Thermostat applications:

  • Select B 3.3L Diesel Engines
  • Select QSB 3.3L Diesel Engines

Note: If your Cummins 3.3L diesel engine is experiencing coolant temperature gauge cycling, replace your existing thermostat with this Cummins 3800884 thermostat. The new Cummins 3800884 thermostat provides a slower coolant response rate to reduce dramatic engine temperature cycling. This slower engine response rate does not affect the engine performance.

The Cummins 3800884 Thermostat on your B/QSB 3.3L Cummins engine allows low-temperature coolant from the radiator into the engine to keep the operating temperature within a predetermined range. Operating a Cummins engine with a bad thermostat will cause the thermostat to get stuck in the open or closed position. A defective thermostat will cause the engine to operate either below the correct operating temperature or above it leading to an overheat condition. If you are currently experiencing any of these symptoms, it's time to replace the Cummins thermostat to alleviate this issue.

The use of Genuine Cummins parts means you get a precision design, state-of-the-art manufacturing, and diligent testing which ensures optimum engine performance at the Cummins factory-specified level. Only Genuine Cummins parts come with a full factory warranty, giving you peace of mind and financial protection.

This 3800884 Replacement Cummins OEM  Thermostat is for the B/QSB 3.3L Cummins engines that are MADE IN THE USA! 

The Cummins 3800884 Thermostat supersedes the:

  • Cummins 1111111 Thermostat for Cummins B/QSB 3.3L Engine

This OEM Cummins Thermostat Benefits:

  • Purchasing Genuine Cummins parts means you get a precision-designed product.
  • Cummins parts are manufactured at state-of-the-art facilities.
  • Strict quality control measures and diligent testing that ensures the replacement parts perform at Cummins factory-specified levels of efficiency,
  • Genuine Cummins parts come with a full factory warranty, giving you peace of mind and financial protection.
  • Only Genuine Cummins parts provide the reliability and durability you need to stay on the road.
  • Engine: Cummins QSB 3.3L | Cummins B 3.3L 
  • Thermostat Opening Temperature: cc°C - xxx°F
  • Item Number: Cummins 3800884
  • Make: Cummins 
  • Model: 
  • Year: 
  • Manufacturer Part No: Cummins 3800884
  • Product Application: Cummins B/QSB 3.3L Engines
  • Height: 3
  • Width :3
  • Brand: Cummins
  • FAQ: Why should you purchase a Genuine Cummins Thermostat for your diesel engine?  Installation of an OEM Cummins 3800884 Thermostat ensures your engine maintains its factory performance, power output levels, function, and straightforward fitment. OEM parts will repair an exact replacement that is trouble-free.
  • Part Number: 3800884
  • Manufacturer: Cummins
  • Product Note: Cummins Parts Are A Non-Returnable Item. Please make sure you have ordered the correct part for your Cummins diesel engine!


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