 |
|||
|
|
|||
| ||||||||||
|
|  MIL-T-62491C
furnished), additional air lines and fittings. The service and emergency couplers shall be mounted
on the front in a protected position providing for ready attachment of air hoses from a towing
vehicle. The service and emergency couplers shall be identified and provided with dummy
gladhand couplers with chains. The system shall not compromise conformance to any Federal
Motor Carrier Safety Regulation referenced herein or to any Federal Motor Vehicle Safety
Standard.
* 3.4.11.5 Increased braking capability. When specified for class 32 and larger diesel engine
driven vehicles (see 6.2), the service brakes shall be augmented by one of the following braking
systems:
(a) An electromagnetic driveshaft retarder
(b) A system which opens all or some of the engine exhaust valves near the end of the
compression stroke, thereby covering vehicle motion to a pumping loss
(c) A controlled gate valve in the exhaust manifold, which produces back pressure on the
engine pistons during the exhaust stroke
(d) When an automatic or semiautomatic transmission is specified, a hydrodynamic retarder
integral with the transmission.
A dash mounted switch shall be provided to activate, modulate, or cut out the brake
augmentation. The switch shall be marked to indicate its position. When active, the system shall
be fully controlled by means of the conventional driving controls to apply retardation during
vehicle deceleration, and to cut it out in the other operating modes. Each of the four systems
shall permit the wrecker loaded to the required GVW to negotiate a 6 percent downgrade without
exceeding 44 km/h (27 mph), within the operating restrictions of the engine and transmission and
without the use of service brakes. For (b) or (c), above, the retarder shall be approved by the
engine manufacturer.
* 3.4.12 Cab. Unless otherwise specified, the chassis manufacturer shall furnish any type of his
standard or optional full width cab. When specified (see 6.2), except for class 10, a cab with a
forward tilting hood and fender assembly, including tilting and locking mechanism shall be
furnished. Tilting shall not interfere with present or future installations of additional equipment,
such as a snowplow or a front mounted winch. When specified (see 6.2), except for class 10, a
tilt cab with tilting and locking mechanism shall be furnished. Tilt cab features shall be in
accordance with the Employee Safety and Health Standards of Federal Motor Carrier Safety
Regulation 399, including the first step height, which shall be not more than 610 mm (24 inches).
Cab doors shall be equipped with locks, operable from inside the cab through mechanical linkage,
with both doors equipped with external, key-operated locks. Drip rails shall be installed above the
cab doors. When the front tires extend beyond the cab fenders, rubber fender extensions
extending at least to the outside of the tire tread shall be furnished. Tilt cabs, with a height from
the ground to the top of the windshield of more than 2030 mm (80 inches), shall include
25
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals