Gates 90K-38121A Serpentine Belt Drive Component Kit

Accessory Belt Drive Kit for Ford and Mercury

The Gates Accessory Belt Drive Kit 90K-38121A is built to restore the accessory belt drive system with OE-equivalent service parts. It combines the belt and tensioner in one application-specific kit, helping address wear across the serpentine drive instead of replacing only the belt.

Compatible With 1982-1987 Ford Mustang and Mercury Capri applications, this kit is a direct-fit service solution for vehicles equipped with factory air conditioning or the listed belt configuration. The Gates 90K-38121A is also referenced by cross-reference part number DBK060910B for the same application.

Key Features

• Accessory Belt Drive Kit from Gates
• Part number: 90K-38121A
• Includes belt and tensioner for the listed application
• OE-equivalent belt construction
• Outside circumference: 91.68 in. / 2329 mm
• Belt top width: 0.807 in. / 20 mm
• Belt 1 part number: K060910
• Tensioner assembly part number: 38121

Product Details

Gates Accessory Belt Drive Kit 90K-38121A is part of the brand’s complete serpentine kit line, created to service the full accessory drive rather than a single wear item. Replacing the belt and tensioner together helps maintain proper belt tracking and tension across the front-end accessory drive, which is important on older Ford Mustang and Mercury Capri belt systems. This kit is specified for 1982-1987 Ford Mustang and 1983-1986 Mercury Capri fitments listed below, including factory A/C and belt-length-specific configurations.

Common Problems This Kit Can Address

• Belt noise from a worn or glazed serpentine belt
• Loss of belt tension from a fatigued tensioner
• Uneven belt wear caused by aging front-end accessory components
• Drive system service issues after replacing only the belt
• Fitment concerns on listed Ford Mustang and Mercury Capri applications

Installation Notes and Tips

Verify the belt length, tensioner part number, and factory A/C configuration before installation. This kit is listed for 1982 Ford Mustang and Mercury Capri with A/C and 91 5/8 in. belt outside circumference, plus 1984-1987 Ford Mustang, 1984-1985 Ford LTD, and 1983-1986 Mercury Capri applications with the notes shown in the fitment list. Follow the included installation instructions and tech tips for accurate routing and tensioner setup.

• Fits 1987 Ford Mustang, N/A; {K060910, 38121}; W/A.C.
• Fits 1986 Ford Mustang, N/A; {K060910, 38121}
• Fits 1986 Mercury Capri, N/A; {K060910, 38121}; W/Factory Inst. A.C.
• Fits 1985 Ford LTD, N/A; {K060910, 38121}; W/Factory Inst. A.C.; W/O Fixed Mounting Stud
• Fits 1985 Ford Mustang, N/A; {K060910, 38121}; W/Factory Inst. A.C.; W/O Fixed Mounting Stud
• Fits 1983-1985 Mercury Capri, N/A; {K060910, 38121}; W/Factory Inst. A.C.; W/O Fixed Mounting Stud
• Fits 1984 Ford LTD, N/A; {K060910, 38121}; W/A.C.
• Fits 1984 Ford Mustang, N/A; {K060910, 38121}; W/Factory Inst. A.C.
• Fits 1982 Ford Mustang, N/A; {K060910, 38121}; W/A.C.; W/91 5/8" Belt O.C.
• Fits 1982 Mercury Capri, N/A; {K060910, 38121}; W/A.C.; W/91 5/8" Belt O.C.

Quality Assurance

Gates is known for OE-style accessory drive components, and this kit is built to service the belt drive system with application-specific parts and installation guidance. Part number 90K-38121A is engineered for the listed Ford Mustang and Mercury Capri fitments and cross-references DBK060910B for the same application.