This manual covers Thomas Skid Steer Loaders, specifically models 135, 137, and 153. These machines are engineered for demanding service and repair applications, featuring a robust hydrostatic drive system designed for reliability and performance. The serial number ranges covered are 137-S/N LE011000 onward and 153-S/N LN002000 onward, ensuring comprehensive support for a wide array of units. The purpose of this English Parts Manual is to provide detailed information for the identification and procurement of components. It includes sections on the Main Frame, Controls, Final Drive Transmission, Hydraulic System, Hydrostatic Drive System, Electrical System, Engine Equipment, and Optional Equipment, along with a Numerical Index for easy part lookup. This manual is designed to assist owners, technicians, and mechanics in maintaining and repairing their Thomas Skid Steer Loaders efficiently.