Dayco 17640 Accessory Drive Belt

Accessory Drive Belt for OE-Style Service

Dayco 17640 is an accessory drive belt built from a synthetic rubber compound for dependable belt drive service. It uses a top-cog construction to help maintain flexibility in accessory drive systems, including fan, power steering, air pump, and air conditioning applications where specified.

With a 0.53-inch top width, 64-inch effective length, and 64.27-inch outside circumference, this black belt is sized for specific OE-style replacement needs. It is engineered to operate across a wide temperature range and meets SAE J636 and SAE J637 standards.

Key Features

• Synthetic rubber compound construction for accessory drive service
• Top-cog belt design for improved flexibility in belt routing
• 0.53-inch top width for the specified drive system application
• 64-inch effective length and 64.27-inch outside circumference
• Rated for temperatures from -35 to 175 degrees
• Built to SAE J636 and SAE J637 standards

Detailed Description

Dayco 17640 is an accessory drive belt intended for vehicles that require a 64-inch class belt with a top-cog profile. The belt’s synthetic rubber compound and cogged construction support consistent operation in accessory drive systems where the belt must wrap pulleys and transfer power to driven components. This part cross-references Gates 9640 and ACDelco 17640 for the same application.

Compatible With 1985-1990 GMC P3500, fan, power steering and air pump; 1985-1989 GMC P2500, fan, power steering and air pump; and 1968 Mercury Cougar, air conditioning and air pump, early. Dayco 17640 is a direct-fit search term for owners servicing these applications and looking for a belt by part number.

What This Belt Helps Address

• Squealing or slipping accessory drive belt noise
• Cracked, glazed, or worn belt surfaces
• Loss of drive to fan, power steering, air pump, or air conditioning components
• Incorrect belt length or profile during replacement
• Service needs on GMC P2500, GMC P3500, and early Mercury Cougar belt drive systems

Installation Notes and Tips

Verify pulley alignment, belt routing, and tensioner condition before installation. Confirm the required belt length, top width, and angle match the original application, especially on GMC P2500 and GMC P3500 accessory drive systems. Inspect related pulleys and driven accessories for wear that could shorten belt life.

Quality Assurance

Dayco manufactures this belt to SAE J636 and SAE J637 standards, with operating temperature capability from -35 to 175 degrees. The Dayco 17640 part number is also useful when matching OE and aftermarket references during service work.