This manual covers the Caterpillar (CAT) GP15N-35N and DP15N-DP35N Series Forklift Trucks, designed for a lifting capacity range of 1500 kg to 3500 kg. These robust machines are engineered for demanding industrial applications, featuring a power shift transmission and robust chassis, mast, and hydraulic systems. The specific generation is identified by serial number ranges, ensuring precise documentation for your unit. The purpose of this service repair manual is to provide comprehensive guidance for the maintenance and repair of your CAT forklift. It details critical procedures for the cooling system, electrical system, fuel system, powertrain, braking system, steering system, and hydraulic system, including the mast and forks. This manual is an essential resource for owners, mechanics, and technicians to ensure the continued reliability, performance, and safety of the GP15N-35N and DP15N-DP35N series forklifts.