Four Seasons 3666R A/C Compressor Kit - Front

Four Seasons PAC-Kit w/ Reman Compressor 3666R

Four Seasons 3666R is a PAC-Kit with a remanufactured A/C compressor for front HVAC applications on select GM and Saab vehicles. It is built for vehicles using a TRSA12B compressor and without rear air conditioning, making it a direct-fit service solution for common compressor replacement jobs.

Key Features

• Four Seasons PAC-Kit w/ Reman Compressor for front A/C service
• Fits vehicles equipped with a TRSA12B compressor
• Application-specific coverage for Chevrolet Trailblazer, GMC Envoy, and Saab 9-7x
• For vehicles without rear A/C
• Part number 3666R for accurate catalog matching

Fitment Details

• Fits 2006-2009 Chevrolet Trailblazer, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor
• Fits 2005-2009 GMC Envoy, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor
• Fits 2005-2009 Saab 9-7x, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor
• Fits 2004-2006 Chevrolet Trailblazer EXT, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor
• Fits 2004-2006 GMC Envoy XL, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor
• Fits 2004-2005 GMC Envoy XUV, front, w/ TRSA12B Compressor; w/o Rear AC; 77548 (Reman Compressor), 83222 (Accum), 38638 (Orifice), 69991 (Flush), 59007 (Oil); PAC-Kit w/ Reman Compressor

What This Compressor Kit Helps Address

• Loss of cabin cooling from a worn or failed A/C compressor
• Noisy compressor operation during A/C engagement
• Reduced refrigerant circulation in the front HVAC system
• Service replacement on Chevrolet Trailblazer and GMC Envoy A/C systems
• Repair needs on Saab 9-7x front air conditioning systems

Installation Notes

Verify the vehicle uses a TRSA12B compressor and does not have rear A/C before ordering. This part number 3666R is listed for front-position applications only, and the fitment notes should be matched to the vehicle’s existing HVAC configuration before installation. This part cross-references 77548 and 83222 for the same application.

Quality Assurance

Four Seasons is a recognized aftermarket brand in HVAC service parts, and the PAC-Kit line groups the compressor with application-specific service components for the listed vehicles. Part number 3666R is cataloged for the exact fitment shown above.