Description:Bevel gear part # 109-4580 is used in the differential that transmits power and compensates for difference in speeds between wheels on either side of the machine and provides for positive traction through use of a locking device.All Cat gears have unique metallurgy compositions tailored to specific applications, with special steel formulas that improve impact resistance and ensure uniformity and proper load transfer. Some Cat gears also undergo proprietary heat treat processes to improve surface, bore, and core hardness. The result is greater durability, which means longer life and better performance.Attributes:• Hardened steel differential bevel gear• Bevel Gear Number of Teeth: 18• Internal Spline Number of Teeth: 30• Pitch Diameter: 145.8 mm (5.74 in)• Inside Diameter: 46.51 mm (1.83 in)• Outside Diameter: 143.66 mm (5.66 in)• Width: 36.44 mm (1.43 in)Application:Consult your owner's manual or contact your local Cat Dealer for more information.