Universal Air EX5900C A/C Expansion Valve - Rear

Brand	Universal Air EX5900C
Position	Rear
Product line	Thermal Expansion Valve
Fits	Chevrolet, GMC, Isuzu, Buick, and Nissan · 42 vehicles

Thermal expansion valve. Regulates refrigerant flow for efficient A/C system performance.

A/C flow restrictor. Helps meter refrigerant through the system with precise control.

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Thermal Expansion Valve for Rear A/C

Universal Air EX5900C is a thermal expansion valve for automotive HVAC systems. It is listed for rear A/C applications on select Chevrolet, GMC, Buick, Isuzu, and Nissan models, including Trailblazer, Envoy, and Frontier fitments.

Key Features

Thermal expansion valve for A/C flow control
Rear HVAC fitment on select GM SUVs and crossovers
Internally equalized design on listed Nissan Frontier applications
Direct fitment references for rear A/C service work
Part number EX5900C for ordering and lookup

Fitment Details

Fits 2003-2009 Chevrolet Trailblazer, rear.
Fits 2003-2009 GMC Envoy, rear. Compatible with rear A/C.
Fits 2003-2008 Isuzu Ascender, rear.
Fits 2004-2007 Buick Rainier, rear.
Fits 2003-2006 Chevrolet Trailblazer EXT, rear.
Fits 2003-2006 GMC Envoy XL, rear. Compatible with rear A/C.
Fits 2004-2005 GMC Envoy XUV, rear. Compatible with rear A/C.
Fits 2002 Chevrolet Trailblazer, N/A.
Fits 2002 Chevrolet Trailblazer EXT, N/A.
Fits 2002 GMC Envoy, rear.
Fits 2002 GMC Envoy XL, rear.
Fits 2001 Nissan Frontier, N/A. Internally equalized; to 07/01/2001.
Fits 1998 Nissan Frontier, N/A. Internally equalized.

What It Helps Address

Inconsistent refrigerant metering at the evaporator
Rear A/C cooling performance concerns
Warm air from rear HVAC vents
Expansion valve restriction or failure during A/C service
System performance issues on listed Trailblazer and Envoy applications

Installation Notes

Verify the vehicle year, make, model, and rear HVAC configuration before ordering. EX5900C is listed for specific rear A/C applications and select internally equalized Frontier fitments, so match the original valve style and service location during diagnosis. Confirm the system is properly evacuated and inspected before replacing the valve.

Quality Assurance

Universal Air EX5900C is cataloged as a thermal expansion valve for the listed applications and is identified by part number EX5900C for accurate fitment lookup and service replacement.

This part fits 42 vehicles

Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

Year	Make	Model	Submodel	Liters	Cylinders	Position	Notes
2009	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2009	GMC	Envoy	SLT	4.2L	L6	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2009	GMC	Envoy	SLE	4.2L	L6	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2008	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2008	GMC	Envoy	SLE	4.2L	L6	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2008	GMC	Envoy	SLT	4.2L	L6	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2008	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2007	Buick	Rainier	—	—	—	Rear	Thermal Expansion Valve
2007	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2007	GMC	Envoy	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2007	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2006	Buick	Rainier	—	—	—	Rear	Thermal Expansion Valve
2006	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2006	Chevrolet	Trailblazer EXT	—	—	—	Rear	Thermal Expansion Valve
2006	GMC	Envoy	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2006	GMC	Envoy XL	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2006	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2005	Buick	Rainier	—	—	—	Rear	Thermal Expansion Valve
2005	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2005	Chevrolet	Trailblazer EXT	—	—	—	Rear	Thermal Expansion Valve
2005	GMC	Envoy	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2005	GMC	Envoy XL	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2005	GMC	Envoy XUV	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2005	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2004	Buick	Rainier	—	—	—	Rear	Thermal Expansion Valve
2004	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2004	Chevrolet	Trailblazer EXT	—	—	—	Rear	Thermal Expansion Valve
2004	GMC	Envoy	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2004	GMC	Envoy XL	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2004	GMC	Envoy XUV	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2004	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2003	Chevrolet	Trailblazer	—	—	—	Rear	Thermal Expansion Valve
2003	Chevrolet	Trailblazer EXT	—	—	—	Rear	Thermal Expansion Valve
2003	GMC	Envoy	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2003	GMC	Envoy XL	—	—	—	Rear	Compatible with rear A/C.; Thermal Expansion Valve
2003	Isuzu	Ascender	—	—	—	Rear	Thermal Expansion Valve
2002	Chevrolet	Trailblazer	—	—	—	N/A	Thermal Expansion Valve
2002	Chevrolet	Trailblazer EXT	—	—	—	N/A	Thermal Expansion Valve
2002	GMC	Envoy	—	—	—	Rear	Thermal Expansion Valve
2002	GMC	Envoy XL	—	—	—	Rear	Thermal Expansion Valve
2001	Nissan	Frontier	—	—	—	N/A	Internally Equalized; To 07/01/2001; Thermal Expansion Valve
1998	Nissan	Frontier	—	—	—	N/A	Internally Equalized; Thermal Expansion Valve
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