THEORY OF OPERATION
The M400W and M400T Skid Steer Loaders (SSL) consist of the following functional systems: engine, powertrain,
chassis, electrical system, hydraulic system, and work tool attachments.
This work package explains how the systems and components of the machine work together. A functional
description is provided for each major component and system.
1. General. The machine is equipped with a 3.2 liter, 4-stroke turbocharged Case F5C diesel engine, with
4 cylinders, generating 74 hp (55kW) (gross) at 2,500 rpm.
2. Fuel System. A flange-mounted, fuel injection pump is mounted in the cylinder block and operated by
3. Cooling System. A belt-driven centrifugal water pump circulates coolant via the internal water passages. The
coolant is radiator cooled and temperature controlled by a conventional thermostat.
4. Lubricating System. An oil pump located in the center of the idler gear sends lubricating oil through a relief
valve to the main oil gallery and then through a bypass oil filter. The rockers are fed through an oil pipe from
the main oil gallery to the cylinder head.
1. Hydrostatic System. The engine provides power to two hydrostatic pumps, one driving each side of the
machine. Each hydrostatic pump drives a corresponding hydrostatic motor. The M400W motor drives both
axles. The M400T motor drives the track directly.
2. Axles. Consist of one-piece, forged induction-hardened high carbon steel.
3. Tracks. The M400W is equipped with steel tracks over rubber tires. The M400T is equipped with steel-
embedded rubber tracks.
4. Parking Brakes.
a. The parking brakes are spring applied, hydraulic release (SAHR) disc.
b. Parking brakes are engaged in three ways:
On/Off Brake button on instrument panel is pressed;
Right hand control handle button is pressed; or
Seat belt is unbuckled and operator gets off seat or engine is stopped.
1. The machine comes with a radial loader arm design and mechanical attachment coupler.
2. The machine has a Rollover Protective Structure/Falling Object Protective Structure (ROPS/FOPS) cab with
heater and air conditioning, which allows for all-weather operation.
3. The air conditioning system uses an evaporator core to exchange heat energy inside the cab. The A/C
compressor circulates R134 through the A/C components.