Aisin THRBM-0004 Engine Coolant Thermostat Housing Assembly

OE Replacement Thermostat Housing

This Aisin engine coolant thermostat housing assembly is an OE-engineered replacement built for exact temperature control. It is a direct-fit solution for select BMW applications and supports consistent coolant regulation in the cooling system.

Key Features

• OE-engineered and manufactured for exact replacement fitment.
• Thermostat housing assembly for integrated cooling system service.
• Exact temperature specification for controlled coolant flow.
• Ultra-Premium OE Replacement line from Aisin.
• Fits select BMW 535i, 535i xDrive, 535i GT, 640i xDrive, 740i, and ActiveHybrid 5 applications.

Detailed Description

Aisin THRBM-0004 is an engine coolant thermostat housing assembly developed as an OE-style replacement for BMW cooling system service. The assembly is specified for exact temperature operation and is listed for multiple BMW platforms, including 535i, 535i xDrive, 535i GT, 640i xDrive, 740i, and ActiveHybrid 5 models. If you are replacing a thermostat housing on a BMW 535i or BMW 640i xDrive, this part number provides a direct replacement reference for the application. Part number THRBM-0004 is also cross-referenced to Beck/Arnley 143-0929 and Gates 34781 for the same application.

What It Helps Address

• Coolant temperature regulation concerns.
• Thermostat housing leakage or housing wear.
• Cooling system service on OE-style BMW applications.
• Temperature control issues tied to thermostat assembly failure.

Installation Notes and Tips

Verify the engine code and cooling system configuration before ordering. Match the part number THRBM-0004 to the vehicle application and confirm the thermostat temperature specification listed for your BMW model. Because this is a housing assembly, inspect adjacent cooling components during replacement to avoid repeat service.

Quality Assurance

Aisin identifies this part as an OE-engineered and manufactured replacement with exact temperature control. The Ultra-Premium OE Replacement line reflects Aisin's focus on direct-fit cooling system components for service applications.