Hayden 5991 Accessory Drive Belt Idler Pulley

Accessory Drive Belt Idler Pulley

Hayden 5991 is an accessory drive belt idler pulley for serpentine belt systems. It is built with a black plastic pulley body, a 6-groove profile, and a 5.1875-inch outside diameter to match common OE-style belt routing requirements.

Compatible With Chevrolet S10, GMC Sonoma, GMC S15, and Chevrolet S10 Blazer applications without air conditioning, this Hayden pulley is a direct-fit replacement for the specified accessory drive belt system positions. The Hayden Pulley line focuses on replacement pulleys and tensioner-style components for belt drive service.

Key Features

• Part number: 5991
• Accessory drive belt idler pulley / tensioner pulley style
• Serpentine belt application with 6 grooves
• Black plastic construction
• 1-inch pulley width and 5.1875-inch outside diameter
• 12.0 mm inside diameter / 0.46875-inch bore diameter
• Meets or exceeds OEM requirements
• Single mounting hole design
• Mounting hardware not included

Detailed Description

Hayden 5991 is an OE-style accessory drive belt idler pulley designed for serpentine belt systems that require a 6-groove pulley with a 1-inch width. Its 131.763 mm outside diameter and 12.0 mm bore dimensions support proper belt tracking and alignment in the accessory drive system. This part cross-references Gates 38034 for the same application.

Fits 1987-1993 Chevrolet S10, without air conditioning; Fits 1991-1993 GMC Sonoma, without air conditioning; Fits 1987-1990 GMC S15, without air conditioning; Fits 1987-1988 Chevrolet S10 Blazer, without air conditioning. For shoppers searching Hayden 5991 for Chevrolet S10 or GMC Sonoma belt drive service, this pulley matches the listed vehicle applications directly.

What It Is Used For

• Replacing a worn or noisy serpentine belt idler pulley
• Restoring proper belt routing in the accessory drive system
• Addressing belt squeal caused by pulley wear or surface damage
• Correcting belt tracking issues related to pulley fit or alignment
• Servicing the belt drive on Chevrolet S10 and GMC Sonoma models without air conditioning

Installation Notes and Tips

Verify pulley diameter, groove count, and bore size before installation. Confirm the vehicle is equipped without air conditioning, as listed in the fitment data. Inspect the serpentine belt, tensioner, and adjacent pulleys for wear before reassembly, and transfer or source mounting hardware separately if required.

Quality Assurance

Hayden 5991 is listed as meeting or exceeding OEM requirements and is intended as a replacement pulley for the specified applications. The Hayden Pulley line is focused on accessory drive belt system components for service and repair use.