Gates 33940 Engine Coolant Thermostat

Gates 33940 Integrated Housing Thermostat

The Gates 33940 integrated housing thermostat is built for precise coolant temperature control in vehicles that use a thermostat and housing assembly. It is an OE-performance replacement for select INFINITI and Nissan applications, including the 2003-2008 INFINITI FX35, 2003-2007 INFINITI G35, 2003-2006 Nissan 350Z, 2003-2004 Nissan Pathfinder, and 2003 INFINITI QX4.

Gates integrated housing thermostat products are developed for modern cooling systems that rely on an integrated design. This part number, 33940, supports accurate engine temperature regulation and is a direct-fit style solution for the listed applications.

Key Features

• Integrated housing thermostat design for select OE-style cooling system layouts
• Start-to-open temperature: 170°F / 77°C
• 3 bolt holes for mounting
• Jiggle pin weep hole: Yes
• Jiggle pin/check valve: Yes
• Outlet inside diameter: 1.205 in
• Outlet outside diameter: 1.375 in
• OE performance rating
• Non-electric thermostat design
• Seal included in the application design

Detailed Description

Gates 33940 is an integrated housing engine coolant thermostat engineered for vehicles that use a combined thermostat and housing assembly. It opens at 170 degrees Fahrenheit, helping regulate coolant flow so the engine can reach and maintain the proper operating temperature. The OE performance rating makes it a practical replacement choice for drivers servicing cooling systems on the INFINITI FX35, INFINITI G35, Nissan 350Z, Nissan Pathfinder, and INFINITI QX4.

This part cross-references Motorad 391-170 for the same application. If you are replacing a thermostat housing on a 2003-2008 INFINITI FX35 or a 2003-2006 Nissan 350Z, Gates 33940 provides the correct integrated housing format for those listed fitments.

What It Helps Address

• Engine running too cool or too warm due to thermostat control issues
• Coolant temperature instability during normal driving
• Cooling system service needs on integrated thermostat housing applications
• Temperature regulation concerns on select INFINITI and Nissan models
• Replacement of a worn thermostat assembly in OE-style housing configurations

Installation Notes and Tips

Verify the vehicle’s thermostat housing style, bolt-hole count, and outlet dimensions before installation. Confirm the 170°F opening temperature matches the original specification for the application. Clean the sealing surfaces thoroughly and inspect the cooling system for contamination, leaks, or damaged hoses before reassembly.

Compatible With: 2003-2008 INFINITI FX35, 2003-2007 INFINITI G35, 2003-2006 Nissan 350Z, 2003-2004 Nissan Pathfinder, and 2003 INFINITI QX4. Use the Gates 33940 part number to confirm the correct integrated housing thermostat for these vehicles.

Quality Assurance

Gates develops aftermarket thermostat solutions for integrated housing applications with OE-style temperature control and fitment focus. The 33940 is built to meet the needs of vehicles that require an integrated housing thermostat rather than a standalone thermostat.