3.4 Chassis components.
3.4.1 Engine. The engine furnished shall be the chassis manufacturer's standard or optional
engine for the commercial model truck which meets or exceeds the requirements of this
* 22.214.171.124 Diesel engine. The vehicle shall be equipped with a liquid cooled, compression
ignition, two-stroke or four-stroke cycle diesel engine, with not less than six cylinders. Engine net
horsepower used in performance prediction calculations shall be determined in accordance with
SAE J1349. The engine shall demonstrate the performance characteristics specified herein when
using diesel fuel conforming to VV-F-800. In addition, when specified (see 6.2), the engine shall
operate satisfactorily on grade JP-4 and grade JP-5 fuel conforming to MIL-T-5624 under
emergency, short duration conditions and on grade JP-8 fuel conforming to MIL-T-83133 under
normal conditions. A power loss when operating JP-4, JP-5 or JP-8 is acceptable.
126.96.36.199 Oil filter. A full-flow or combined full-flow and bypass oil filter with replacement
element shall be furnished.
188.8.131.52.1 Oil cooler. An engine oil cooling system shall be furnished.
* 184.108.40.206 Governor. An engine governor shall be furnished and set and sealed to limit the
engine to the engine manufacturer's maximum recommended operating speed.
* 220.127.116.11 Cooling system. The cooling system shall maintain the engine coolant at a
temperature below the boiling point with the vehicle loaded to rated GVW and operated at an
altitude of 10,000 feet above sea level or in an ambient air temperature of not less than
125 degrees Fahrenheit (°F). The coolant system shall include a surge tank or a coolant recovery
reservoir of not less than two-quart capacity.
18.104.22.168 Coolant temperature control. Thermostatic control of engine coolant temperature
shall be provided. The control shall include partial thermostatic control of coolant flow through
the radiator and thermostatically controlled radiator shutters, or complete thermostatic control of
all coolant flow through the radiator. On tilt cab models, a radiator servicing access door shall be
provided to allow verification of the coolant level.
* 22.214.171.124 Fan clutch. A fan clutch shall be provided. The fan clutch shall reduce fan speed
automatically when the fan is not required for engine cooling. The fan clutch shall be asbestos
* 126.96.36.199 Power plant heaters and fuel warmer. When specified (see 6.2), a coolant heater, an
engine oil heater, and a fuel warmer shall be provided. Heaters shall operate on 110-volt
alternating current (ac), and shall be wired through a junction block, including a fuse or circuit
breaker, to a single three-pronged (male), weatherproof, slave receptacle for receiving external