Dorman 34172 A/C Compressor Bypass Pulley

Brand Dorman 34172
Material Aluminum bracket
Material Plastic pulley
Outside Diameter 135
Mounting Hardware Included No
Belt Type Serpentine
Mounting Bracket Included Yes
Compressor Type Ltr4
Installation Instructions Included Yes
Number of Pulleys Included 1
Package Contents Pulley and bracket
Fits Ford and Mazda · 10 vehicles

Bypass pulley solution. Lets the original equipment drive belt stay in use while bypassing an inoperable A/C compressor.

Aluminum bracket. With a plastic pulley for a practical, lightweight design.

Bracket included. Package contains the pulley and bracket for a complete assembly.

Cross-references SK34172 for the same application. See all 1.

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Dorman 34172 A/C Compressor Bypass Pulley

Dorman 34172 is an A/C compressor bypass pulley for vehicles that need to keep the original serpentine belt routing while bypassing an inoperable compressor. It uses an aluminum bracket with a plastic pulley and includes installation instructions for a straightforward repair path.

Key Features

  • Bypasses a failed A/C compressor while retaining the OE drive belt
  • Aluminum bracket with plastic pulley construction
  • Designed for serpentine belt systems
  • Includes mounting bracket and installation instructions
  • Outside diameter: 135 mm
  • Configured for Ltr4 compressor applications

Product Details

This Dorman 34172 bypass pulley is a practical solution when the original compressor is no longer operational but the vehicle still needs a proper belt path. It replaces the compressor’s function in the accessory drive so the serpentine belt can continue to run the engine accessories without routing changes. This part cross-references SK34172 for the same application. It is a direct-fit service part for 1994-1997 Ford Aspire and 1990-1995 Mazda Protege applications, including Ford Aspire and Mazda Protege vehicles that require compressor bypass service.

Common Problems It Can Help Address

  • Broken or seized A/C compressor pulley assembly
  • Loss of belt routing after compressor failure
  • Need to keep the serpentine belt in service without replacing the full A/C system
  • Accessory drive noise caused by an inoperable compressor
  • Vehicle downtime while planning a larger HVAC repair

Installation Notes and Tips

Verify the compressor type, belt routing, and pulley alignment before installation. This part is intended for serpentine belt systems and includes the bracket and instructions needed for setup. Mounting hardware is not listed as included, so confirm reuse or replacement requirements during service. For fitment, use the vehicle-specific application: Fits 1994-1997 Ford Aspire, N/A; Fits 1990-1995 Mazda Protege, N/A.

Quality Assurance

Dorman supplies service replacement components engineered for repair applications where restoring drivability matters. Part number 34172 is built as a practical bypass solution for selected Ford Aspire and Mazda Protege models when the original A/C compressor is no longer usable.

This part fits 10 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
1997FordAspireN/A
1996FordAspireN/A
1995FordAspireN/A
1995MazdaProtege1.8LL4N/A
1994FordAspireN/A
1994MazdaProtegeN/A
1993MazdaProtegeN/A
1992MazdaProtegeN/A
1991MazdaProtegeN/A
1990MazdaProtegeN/A
Directly replaces or cross-references 1 part number
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
SK34172