Four Seasons 39370 A/C Expansion Valve - Front

Mercedes-Benz A/C Expansion Valve

Four Seasons 39370 is a block-type A/C expansion valve for R134A systems. It is built from aluminum and meets or exceeds OEM requirements for direct replacement service on select Mercedes-Benz ML, GL, and R-Class applications.

Use this Four Seasons expansion valve when servicing Mercedes-Benz ML500, ML350, GL450, or R350 air conditioning systems that require precise refrigerant metering. The Four Seasons Expansion Valve line is focused on restoring proper evaporator feed control in factory-style HVAC layouts, and part number 39370 is specified for vehicles with the matching block-type configuration.

Key Features

• Four Seasons part number 39370
• Block-type A/C expansion valve for R134A refrigerant systems
• Aluminum construction and aluminum finish
• Meets or exceeds OEM specifications
• Female FIO insert O-ring liquid and suction connections
• Designed for Mercedes-Benz HVAC applications with front or N/A listed positions
• W/O solenoid style
• Includes OE-style green O-ring service points referenced by the manufacturer data

Detailed Description

This expansion valve regulates refrigerant flow into the evaporator so the HVAC system can maintain proper cooling performance and superheat control. Four Seasons 39370 is listed for Mercedes-Benz ML500, ML550, ML350, ML450, ML63 AMG, ML320, GL350, GL450, GL500, GL550, R350, R500, R550, and R63 AMG applications across the 2006-2014 model years, including front-position systems where specified. This part cross-references Genuine 1648300084 and UAC EX9724C for the same application.

What It Helps Address

• Weak or inconsistent cabin cooling
• Incorrect refrigerant metering at the evaporator
• HVAC performance loss after A/C service
• Temperature fluctuation in Mercedes-Benz ML, GL, and R-Class systems
• Expansion valve restriction or wear in R134A setups

Installation Notes and Tips

• Verify the vehicle’s refrigerant type is R134A before installation.
• Confirm the block-type valve layout and matching inlet/outlet sizes before ordering.
• Replace and lubricate O-rings as needed during A/C service to help maintain sealing integrity.
• Evacuate and recharge the system according to factory service procedures after installation.
• Check for leaks and verify vent temperature and system pressures after repair.

Quality Assurance

Four Seasons 39370 is manufactured to meet or exceed OEM requirements for the listed Mercedes-Benz applications. The Four Seasons Expansion Valve product line is built for OE-style replacement service in automotive HVAC systems.