The 3406 is a stock diesel engine that is inside many heavy industrial vehicles manufactured by Caterpillar, such as its skid steers and front loaders. The Caterpillar features a six-cylinder, fuel-injected engine. The 3406 flywheel absorbs mechanical energy as it rotates and compensates for torque fluctuations. The torque converter is a hydrodynamic fluid coupling that's used to transfer power from the combustion engine to the transmission. Both the flywheel and the torque converter are tightened to specific torque tightness, measured in foot pounds.
The 3406 flywheel rotates, or spins, fluidly and smoothly at all times, regardless of changes in the engine's torque output. The Caterpillar 3406 flywheel produces 99 flywheel horsepower.
The Caterpillar 3406 flywheel, which is part number 4P4797, weighs approximately 75 pounds and is located at the bottom rear section of the engine. The 3406 flywheel bolt is tightened to approximately 70 foot pounds.
Torque Converter Basics
The drive control on the 3406 uses a torque converter shifting system, as opposed to a clutch system. The torque converter on the 3406 is located between the rear of the engine and the transmission.
Torque Converter Specifications
The 3406 S6S produces approximately 192 foot-pounds of torque at 1,700 rpm. The torque converter bolts are tightened to 85 foot pounds.