Four Seasons 3921N A/C Compressor Kit

Four Seasons PAC-Kit w/ New Compressor 3921N

Four Seasons 3921N is an A/C compressor kit built for specific 2002-2004 Chevrolet Silverado HD and GMC Sierra HD applications. It is listed as a PAC-Kit with a new compressor and is matched to detailed OE-style configuration requirements for the compressor type, orifice tube diameter, and related HVAC components.

Key Features

• Four Seasons PAC-Kit w/ New Compressor for targeted HVAC service
• Part number 3921N for easy catalog matching
• Application-specific coverage for Chevrolet Silverado 2500 HD, Silverado 3500, GMC Sierra 2500 HD, and Sierra 3500
• Configured for 10S17F and 10S20F compressor applications, depending on vehicle setup
• Requires 13mm orifice tube diameter on listed applications
• Notes include black orifice tube and drier clocking details where specified

Detailed Description

This Four Seasons A/C compressor kit is cataloged for 2002-2004 Chevrolet Silverado HD and GMC Sierra HD trucks with exact fitment notes that matter during HVAC repair. The 3921N listing covers vehicles with specific compressor families, including 10S17F and 10S20F, and references related components such as the accumulator, orifice tube, flush, and oil specifications for the application. If you are servicing a 2004 Chevrolet Silverado 2500 HD, 2004 GMC Sierra 3500, or another listed truck, verify the compressor type and option package before ordering.

This part cross-references OE-style service references 78348 and 83211 for the same application.

What It Helps Address

• Weak or failed A/C compressor operation
• No cold air from the HVAC system
• Compressor noise, seizure, or internal wear
• System contamination after compressor failure
• Incorrect compressor match on Silverado HD and Sierra HD service jobs

Installation Notes and Tips

• Confirm the vehicle year, make, model, and compressor type before installation.
• Match the listed orifice tube diameter and option notes, including ambulance package and Denso compressor references where applicable.
• Inspect the accumulator, orifice tube, and system cleanliness before charging the system.
• Follow the specified flush and oil requirements for the application.
• Verify drier clocking and fitting style on 2004 listings before final assembly.

Quality Assurance

Four Seasons catalogs this PAC-Kit under part number 3921N for application-specific HVAC service on the listed Chevrolet Silverado HD and GMC Sierra HD trucks. Use the fitment notes to confirm the exact configuration before installation.