Mercedes W204 Transmission Oil Line Hose Tube Pipe Automatic Gearbox A6421804030

Mercedes W204 Transmission Oil Line Hose Tube Pipe Automatic Gearbox is a transmission oil cooling system component designed for models with an automatic transmission. As part of the Oil coolers and lines group, it is responsible for the safe supply and return of oil to the cooler, stabilizing the transmission's operating temperature. This original used part is a sensible choice for drivers looking for a technically matched solution at an attractive price.

Specifications and technical data

• SKU: A6421804030
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6421804030
• Substitutable numbers: A6421804030, A 642 180 40 30
• Gearbox type: Automatic
• Category: Oil Coolers & Lines

Purpose and function in the drivetrain

The described oil line is designed to work with the automatic transmission in the Mercedes W204 class. It is responsible for transporting transmission oil between the gearbox and the cooler, which helps maintain a stable operating temperature and reduces the risk of component overheating.

A properly selected transmission oil line:

• ensures a leak-free flow of the working medium in the transmission cooling system,
• helps maintain proper automatic transmission operating parameters under load,
• reduces the risk of oil pressure drops due to leaks or line damage.

Benefits of using an original oil line

The original oil line from the Oil coolers and lines group is structurally matched to the body geometry and drivetrain of the Mercedes W204. This means proper line routing, correct length and diameter, as well as compatible connection ends, which facilitates installation and eliminates the need for modifications.

In practice, this translates into:

• stable operating conditions for the automatic transmission in city traffic and on the highway,
• reduced risk of oil leaks from connections,
• more predictable transmission behavior during gear changes.

Characteristics of the used component

The offered line comes from dismantling and is sold as a used part. Such components are a popular choice for oil cooling system maintenance when the goal is to maintain the original design while optimizing costs. A used element allows for an economical repair without sacrificing factory-fitment for a specific model.

Before installation, a standard visual inspection and verification of connection tightness after starting the vehicle are recommended, in accordance with service procedures for oil systems.

Cooling system cooperation and operation

The automatic transmission oil line works in direct connection with the oil cooler and other lines in the system. Its proper condition affects the durability of the transmission, especially in conditions of high ambient temperatures and intensive use. Maintaining the tightness and patency of the lines is one of the key elements of preventive maintenance for automatic transmissions.

To better understand the impact of temperature on the cooling system and components working with the cooler, it is worth reading the guide: Summer heat vs. cooling system: used radiators and fans as a guarantee of savings.

Expanding the oil cooling system in a Mercedes

If you are planning a comprehensive repair or upgrade of the oil cooling area in your Mercedes and need other elements from the same group, such as additional lines, return lines, or connection elements, check the available parts in the Mercedes oil coolers and lines category.