Gates 90K-38121 Serpentine Belt Drive Component Kit

Accessory Belt Drive Kit for Ford Mustang

The Gates 90K-38121 Accessory Belt Drive Kit restores the serpentine drive system with OE-equivalent components for a direct-service approach. It is built for 1988-1993 Ford Mustang applications with factory-installed air conditioning, helping address belt wear and front-end accessory drive issues in one service.

Gates Accessory Belt Drive Kit products are engineered as complete serpentine service solutions. This line is focused on replacing the belt and related drive components together so the accessory system is serviced as a unit, rather than addressing only one worn part.

Key Features

• Part number: 90K-38121
• Accessory Belt Drive Kit for serpentine drive service
• Includes an OE-equivalent belt and tensioner
• Belt 1 part number: K060905
• Tensioner assembly part number: 38121
• Belt outside circumference: 90.873 in. / 2308 mm
• Belt top width: 0.807 in. / 20 mm
• Fits 1988-1993 Ford Mustang, N/A, with factory-installed A.C.

Detailed Description

The Gates 90K-38121 serpentine belt drive component kit is intended for Ford Mustang models from 1988 through 1993 with factory-installed air conditioning. By servicing the belt and tensioner together, this kit supports a more complete repair of the accessory drive system and helps reduce repeat service caused by replacing only the belt. The 90K-38121 reference is also useful when cross-checking the correct serpentine drive service part for this Mustang application.

This part cross-references Monroe Shocks & Struts (e.g., DBK060905B) for the same application.

What It Helps Address

• Squealing or chirping from a worn serpentine belt
• Loss of belt tension from a fatigued tensioner
• Uneven belt tracking caused by accessory drive wear
• Repeat belt replacement when related drive components are not serviced
• Accessory drive noise on 1988-1993 Ford Mustang models with factory A.C.

Installation Notes and Tips

Verify belt routing, tensioner alignment, and pulley condition before installation. Confirm the vehicle is a 1988-1993 Ford Mustang with factory-installed A.C. and match the existing belt dimensions and tensioner reference to 90K-38121 before service. Follow the included installation instructions and tech tips for accurate fitment and setup.

Quality Assurance

Gates markets this Accessory Belt Drive Kit as a complete serpentine service solution with OE-equivalent belt construction and application-specific components for accurate repair on the listed Ford Mustang vehicles.