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Gates · Cooling System
k121039hd
In stock · ships from Knoxville
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.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 3 applications
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All confirmed applications for this part number.
Caterpillar
Caterpillar
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.
Part data verified against 3 catalog sources
Numbers this part supersedes or interchanges with. Showing 1 of 1.
Different year, make, or config? Get a confirmation against your truck in under a minute.
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.
Part Number: k121039hd
belt
Vendor: Cumberland Auto Parts
Dealer: Knox Trailers
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