Product Description
KB799559X – DRIVEMASTER FAN CLUTCH (WESTERN STAR / CUMMINS ISX)
PART NUMBER(S):
Fleet Products: KB799559X (Remanufactured) | OE: Horton 99A9559, 79A9559 | Kit Masters 99559
DESCRIPTION:
Model: Horton DriveMaster On/Off
Vehicles: Western Star 4900 (2010–2013)
Engine: Cummins ISX
• Fan Drive Ratio: 2:1
• Back Pulley Diameter: 7.83″
• Overall Length: 12.60″
• Belt Configuration: 12PK
• Belt Groove Location: 6.65″
• Bolt Circle: 3.5″
• Fan Pilot Diameter: 2.56″
• Fan Blade Stud Length: 0.81″
• Vertical Mounting Distance: 1.42″
• Horizontal Mounting Distance: 4.06″
Applications:
Designed for Western Star trucks with Cummins ISX engines, this Horton DriveMaster fan clutch delivers consistent cooling for heavy-duty applications. Built for reman reliability, it reduces downtime and supports linehaul and vocational fleets requiring dependable temperature control.
CROSS-REFERENCE(S):
21596045, 22113077, 3443-99559, 3912-79A96442, 706304AT, 79A9559, 79A9559-2, 79A9595, 79A9644-2, 98A9552-2, 98A95522, 98A9559, 98A9595, 98A9644-2, 99A8110, 99A9559, 99A9559-2, 99A9644-2, ABP N20 99559, ABPN2099559, F17-1014M03, F17-6014M06, F17-6017M28, FC7996442, FLT99559, HOR79A9595, HOR98A9595, HOR99A8110, HOR99A9595, KM N20 99559, KMI99559, KMN2099559, RX79A9644-2RMAN, RX79A96442RMAN, RX79A96442RMANRF
A cross-reference listing means this part is a suitable replacement for the part numbers listed. Please confirm all dimensions match your application before installing.
IMPORTANT INSTALLATION NOTES:
✔ Verify all mounting dimensions and fan blade compatibility prior to install
✔ Recommended specifically for heavy-duty truck applications with Cummins ISX engines
✔ Ensure correct belt groove alignment and pulley fitment
✔ Apply proper torque and check fan hub alignment before startup
Drivemaster On/Off Repair Kits:
- Minor Seal Repair Kit: 294346
- Major Repair Kit: 294351
- Super Repair Kit: 295568, 295575, 299985, Q299999 (Universal)
- Lining Kit: 294349
SOLD AS REMANUFACTURED – CORE RETURN REQUIRED
Built to OEM standards — thoroughly cleaned, inspected, and tested to ensure durability, performance, and reliability in demanding applications.
SUPPORT & ORDERING
For technical support, installation guidance, or to confirm fitment, call 1-877-243-0442 or email sales@fleet-products.com
WHY CHOOSE Fleet Products | KBR - Heavy Duty Truck & Trailer Parts?
- Canadian-owned since 1985
- Trusted by fleets, mechanics, and B2B partners across North America
- Fast, Reliable Shipping Across North America
- Competitive pricing with Core Return Refunds
- Price Match Guarantee – Find a better price? We’ll beat the difference by 10%!