BMW E90 E91 LCI E92 F01 N57 Oil Cooling Pipe Hose Radiator 8509432

The BMW E90 LCI E92 F01 N57 Transmission Oil Hose is an original component of the automatic transmission lubrication system, designed for BMW models with the N57 engine. Thanks to its factory geometry and precise fit for specific body series, the hose ensures stable transmission oil flow and proper cooperation with the oil cooler.

Specifications and technical data

• SKU: 8509432
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8509432
• Substitutable numbers: 17228509432, 8509432, 8509436, EM, 51357129736, 7129736
• Category: Oil Coolers & Lines

Purpose and Function in the Oil Cooling System

The transmission oil hose, part of the Oil Coolers and Hoses group, is responsible for transporting the lubricating medium between the gearbox and the heat exchanger. In BMW vehicles with the N57 unit, maintaining a stable transmission oil temperature is crucial for:

• maintaining proper operating pressure in the automatic transmission,
• reducing wear on friction components,
• preserving smooth and precise gear changes,
• extending the lifespan of the entire drivetrain.

A properly selected oil hose minimizes the risk of leaks, pressure drops, and oil overheating, which translates to stable transmission operation across a wide range of loads.

Advantages of Using an Original BMW Hose

This component, originating from the BMW OE group, has been specifically designed for the transmission oil system in E90 LCI, E92, and F01 models with the N57 engine. This means:

• factory-perfect fit to mounting points and routing in the engine bay,
• maintenance of the correct oil flow diameter and cross-section,
• compatibility with original quick connectors and seals,
• consistency with the operating parameters of the oil cooling system.

This ensures a streamlined installation process without the need for modifications, and the system retains the parameters intended by the manufacturer.

Condition, Verification, and Preparation for Installation

The hose is offered as a used part, allowing for an economical repair of the oil system while maintaining the original BMW specifications. Before being offered for sale, the part is verified for:

• hose integrity and absence of mechanical damage,
• condition of the connection spigots,
• absence of visible deformations affecting oil flow.

A hose prepared in this manner is a practical solution for replacing a damaged or leaking component in the transmission oil cooling system.

Integration with the Oil Cooling System and Operation

In BMW vehicles with the N57 engine, the transmission oil hose works in conjunction with the oil cooler, ensuring stable thermal conditions during city and highway driving. A properly functioning hose:

• reduces the risk of gearbox overheating under heavy loads,
• supports even oil distribution throughout the system,
• allows for predictable transmission behavior in comfort and dynamic modes.

For users planning long-term vehicle ownership, replacing a worn hose with a functional OEM part is a sensible investment in the trouble-free operation of the drivetrain.

System Expansion and Auxiliary Materials

If you are planning a comprehensive repair or upgrade of the transmission lubrication and cooling system in your BMW and require other components from the same group, such as additional oil hoses, transmission oil coolers, or system connectors, please check the available parts in the BMW Oil Coolers and Hoses category.

To better understand the impact of operating temperature on the durability of the cooling and lubrication system, it is worth reading the guide Summer Heat vs. Cooling System: Used Coolers and Fans Guarantee Savings, which discusses practical aspects of selecting and operating components responsible for heat dissipation in a car.