This comprehensive workshop service repair manual provides detailed instructions and illustrations for servicing and repairing Allison AT 540, 542, 543, 545, 1542, and 1545 automatic transmissions. The manual covers a wide range of topics, including general information, description and operation, mounting, input drive, transmission housing, torque converter assembly, lockup clutch, oil pump assembly, forward clutch and turbine shaft, planetary gear unit, speedometer drive, speed sensor wheel, governor, modulator, vacuum modulator, mechanical modulator, electric modulator, oil pan and filter, hydraulic retarder, main control valve assembly, hydraulic system, system functions, preventive maintenance, disassembly of transmission, rebuild of subassemblies, wear limit data, spring data, and troubleshooting. This manual is designed for both do-it-yourself mechanics and experienced professionals, providing step-by-step instructions and diagrams to guide you through each service, repair, and maintenance procedure. With its detailed illustrations and comprehensive information, this manual is an invaluable resource for keeping your Allison transmission operating at peak performance.

The Allison AT 540, 542, 543, 545, 1542, and 1545 gearboxes are a family of heavy-duty automatic transmissions designed for use in a wide range of commercial trucks and other heavy-duty vehicles. These transmissions are known for their reliability, durability, and fuel efficiency, making them a popular choice for applications such as long-haul trucking, construction, and mining. The different models within this family offer varying torque capacities and gear ratios, allowing for tailored performance to meet individual vehicle and application requirements. For example, the AT 540 is the most basic model, while the AT 545 offers a higher torque capacity and advanced features. The "N" designation indicates a transmission with a neutral start feature, while the "R" designation signifies a transmission equipped with a retarder. The "P" designation on the 1542P and 1545P models indicates a transmission specifically engineered for use with a power take-off (PTO) system. The Allison AT 540, 542, 543, 545, 1542, and 1545 transmissions are built with robust construction featuring heavy-duty components and advanced technology. Their electronic controls provide seamless shifting and optimal performance, while the patented torque converter technology delivers superior acceleration and fuel economy. These transmissions are also designed with a focus on operator comfort, offering smooth and quiet operation. The availability of a wide range of optional features, such as retarders, overdrive gears, and PTOs, allows users to tailor the transmissions to their specific requirements. The Allison AT 540, 542, 543, 545, 1542, and 1545 gearboxes are a testament to Allison Transmission's commitment to delivering reliable and durable automatic transmissions that enhance vehicle performance and fuel efficiency for a wide range of commercial applications.