Four Seasons 38812 A/C Expansion Valve - Rear

Four Seasons 38812 Expansion Valve Overview

Four Seasons Expansion Valve 38812 is a block-type A/C expansion valve for R134A systems. Built from aluminum and specified for rear HVAC service, it helps regulate refrigerant flow in applications such as the Ford Expedition, Lincoln Navigator, Ford Windstar, Mercury Villager, and Nissan Quest.

Four Seasons 38812 is an OE-style replacement expansion valve that meets or exceeds OEM requirements and uses O-ring style female fittings for the suction and liquid connections. This part number is commonly searched for rear A/C repair on 1993-2002 Ford, Lincoln, Mercury, and Nissan minivan and SUV applications.

Key Features

• Part number: 38812
• Brand line: Four Seasons Expansion Valve
• Block-type A/C expansion valve for R134A refrigerant
• Aluminum construction with aluminum finish
• Rear HVAC application with 1.5 tonnage rating
• Female O-ring suction and liquid fittings
• Meets or exceeds OEM specifications
• Style: w/o solenoid
• Super heat setting: 5.000
• Compatible with rear A/C service on Ford Expedition, Lincoln Navigator, Ford Windstar, Mercury Villager, and Nissan Quest

Product Details

Four Seasons 38812 is an A/C expansion valve used to meter refrigerant into the evaporator and maintain proper system operation in rear HVAC circuits. The valve features No. 10 suction inlet and outlet threads with 7/8"-18 thread type, plus No. 6 liquid inlet and No. 8 liquid outlet threads with 5/8"-18 and 3/4"-18 thread types. It uses FOR-style O-ring connections and includes the specified green O-ring sealing points for the listed connection sizes. If you are replacing a rear expansion valve on a Ford Expedition, Lincoln Navigator, Ford Windstar, Mercury Villager, or Nissan Quest, Four Seasons 38812 is a direct-fit service part for the confirmed applications.

This part cross-references Monroe Shocks & Struts (e.g., 182271) for the same application.

Common Repair Symptoms

• Rear A/C vents blowing warm air
• Erratic refrigerant metering at the evaporator
• Low cooling performance in the rear HVAC system
• Restricted or uneven refrigerant flow through the expansion valve
• Service replacement for a leaking or failed rear A/C expansion valve

Installation Notes and Tips

Verify the rear HVAC configuration and match the suction and liquid fitting sizes before installation. Replace the valve only after the system has been properly evacuated, and inspect the mating O-ring sealing surfaces for wear or contamination. Confirm refrigerant type is R134A and follow the vehicle service procedure for the Ford Expedition, Lincoln Navigator, Ford Windstar, Mercury Villager, or Nissan Quest application.

Quality Assurance

Four Seasons 38812 is built as an OE-replacement expansion valve and is listed as meeting or exceeding OEM requirements for the specified applications.