Four Seasons 39110 A/C Expansion Valve - Rear

Four Seasons 39110 Expansion Valve Overview

Four Seasons 39110 is a block-type A/C expansion valve for R134A systems, built with an aluminum body and OE-style insert O-ring connections. It is specified for rear HVAC service on select Oldsmobile, Pontiac, and Pontiac minivan applications, including 1997-2000 Oldsmobile Silhouette, 1999-2000 Pontiac Montana, and 1997-1998 Pontiac Trans Sport.

As part of the Four Seasons Expansion Valve line, this component is made for precise refrigerant metering in the rear air conditioning circuit. The design meets or exceeds OEM requirements and uses the correct inlet and outlet port sizing for direct replacement service.

Key Features

• Part number: 39110
• Four Seasons Expansion Valve line
• Block-type A/C expansion valve
• Aluminum construction with gold finish
• R134A refrigerant system application
• Rear HVAC position
• Female FIO insert O-ring liquid and suction connections
• Meets or exceeds OEM specifications
• OE-style fitment for rear A/C service on Oldsmobile Silhouette, Pontiac Montana, and Pontiac Trans Sport

Product Details

Four Seasons 39110 regulates refrigerant flow into the evaporator to help maintain proper system pressure and cooling performance in rear air conditioning setups. The valve is configured without a solenoid and uses factory-style port dimensions, including No. 10 suction inlet, No. 12 suction outlet, No. 6 liquid inlet, and No. 8 liquid outlet thread diameters. It also includes the specified green O-ring sealing points for the listed application.

This part cross-references UAC EX5596C for the same application. If you are servicing a 1997-2000 Oldsmobile Silhouette rear A/C system, a 1999-2000 Pontiac Montana rear HVAC circuit, or a 1997-1998 Pontiac Trans Sport rear expansion valve, Four Seasons 39110 provides the correct replacement format for those vehicles.

Common Problems This Part Can Address

• Rear A/C air that is not cooling properly
• Refrigerant flow restriction at the evaporator inlet
• Incorrect system pressure caused by a worn expansion valve
• Uneven rear cabin temperature control
• Leak concerns at the valve-to-line sealing surfaces

Installation Notes

Verify the vehicle’s rear HVAC configuration, refrigerant type, and port style before installation. Replace the valve only after the system has been properly recovered and inspected, and confirm that the mating lines and sealing surfaces are clean and undamaged. Use the correct service procedures for R134A systems and check for proper operation after evacuation and recharge.

Fits 1997-2000 Oldsmobile Silhouette, rear. Fits 1999-2000 Pontiac Montana, rear. Fits 1997-1998 Pontiac Trans Sport, rear.

Quality Assurance

Four Seasons 39110 is listed as meeting or exceeding OEM requirements for the specified applications, supporting direct replacement service in rear A/C systems.