The Sisu Diesel 320, 420, 620, and 634 Engine All Service Repair Manual provides comprehensive guidance for maintaining and repairing these powerful engines. This manual delves into every aspect of these engines, offering detailed information on general maintenance procedures, troubleshooting common issues, and executing thorough engine service and repair. It equips you with the knowledge to tackle a wide range of engine-related tasks, from basic maintenance to complex repairs.

The manual covers essential areas such as engine service and repair, transmission service and repair, brake system, wiring diagrams, electrical system, suspension, periodic lubrication, steering, cooling system, fuel injection/fuel system, emission system, engine control system, chassis and body, restraint system, and axles. With its comprehensive scope, this manual empowers you to perform repairs and maintenance with confidence, saving you time and money in the long run.

The Sisu Diesel 320, 420, 620, and 634 are a series of heavy-duty trucks manufactured by Sisu Auto, a Finnish company known for its robust and reliable vehicles. These trucks were primarily designed for demanding applications in various industries, including construction, forestry, and transportation. The engine lineup for these models included powerful and durable diesel engines, delivering impressive torque and horsepower for tackling challenging tasks.

The Sisu Diesel 320, 420, 620, and 634 models were equipped with a range of features essential for heavy-duty operations. These included sturdy chassis construction, robust axles, and heavy-duty transmissions capable of handling significant loads and off-road conditions. These trucks were known for their exceptional durability and reliability, built to withstand harsh environments and demanding working conditions. The Sisu Diesel 320, 420, 620, and 634 were popular choices for businesses seeking dependable and long-lasting trucks for their operations. Despite their age, these trucks are still highly sought after in the used truck market, demonstrating their enduring value and legacy. Their reputation for reliability and ruggedness continues to make them a popular choice for those needing a truck that can handle tough jobs.