belt

Name: k121039hd - belt
Brand: Gates
SKU: k121039hd
Price: 127.22 USD
Availability: InStock

This is a heavy-duty 12-rib serpentine belt (Gates FleetRunner HD K121039HD) with an outside circumference of 104.5 inches and a top width of approximately 1.65 inches. It drives engine accessories like the alternator, water pump, and air conditioning compressor on commercial trucks. The belt is made from long-life EPDM rubber with polyester tensile cords, designed to withstand high heat, ozone, and coolant exposure. Replace it when signs of cracking, glazing, or excessive wear appear, or according to your manufacturer's service interval.

$127.22

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Verified fitment

Peterbilt 357 (2007) with Caterpillar C15 Diesel
Peterbilt 378 (2007) with Caterpillar C15 Diesel
Peterbilt 379 (2007) with Caterpillar C15 Diesel

These fitments are confirmed for the listed model years and engine; however, this belt follows the 12PK2640 industry standard and may also fit other heavy-duty applications. Always verify belt routing, tensioner type, and exact engine/accessory configuration before installation.

Specifications

SKUk121039hdBrandGatesSupplierPost OnsiteCategoryCooling SystemAvailabilityIn StockBelt TypeAutomotive V-Ribbed Belt (Heavy Duty)SectionKNumber of Ribs12Top Width1.65 in (42 mm)Outside Circumference104.5 in (2654 mm)Effective Length103.94 in (2640 mm)Belt MaterialEPDMCord MaterialPolyesterIndustry Standard12PK2640