3.13.2 Brake wiring. Electric brakes shall be wired to the auxiliary circuit of the SAE J560
seven-conductor electrical connector. All wiring shall be properly mounted and secured with
clamps. Wiring shall be heavy-wall thermoplastic insulated cable and shall be enclosed in conduit.
3.13.3 Electrical cable. Unless otherwise specified (see 6.2), a coiled electrical cable
conforming to SAE J1067, with a cable plug at each end conforming to SAE J560, shall be
provided. Both plugs shall be equipped with a grip for withdrawing from connector sockets.
Stowage provisions shall have an anti-theft feature. Means of hanging the cable with the plugs
pointing down shall be provided. The cable, when fully extended, shall be not less than 3 feet
longer than the distance from the trailer electrical receptacle to the ball hitch.
220.127.116.11 Turn signals. Turn signals conforming to SAE J588 shall be furnished.
3.14 Trailer body and frame.
3.14.1 Body and frame construction. The trailer shall be equipped with a body and frame of
all steel welded construction, with each main frame member in one piece without splices or joints.
A sufficient number of full-width crossmembers shall be furnished to assure stability with the
trailer fully loaded. All parts of the chassis frame, where welding is required, shall be electrically
welded. Body floor and side panels shall be of adequate gage and construction so as to support
trailer payload specified without evidence of deformation or permanent set. The body side and
front panels shall be flanged outward into a box section at the top. The front panel shall be
provided with 2 tie down devices. Each side panel shall be provided with 4 tie down devices. Tie
down devices shall be welded to the cargo body and located near the upper top of each panel.
3.14.2 Tailgate. A tailgate shall be furnished. The tailgate shall be hinged at the floor level of
the cargo body. The inside surface of the tailgate shall be covered with safety steel tread plate.
When the tailgate is in closed position, the height of the tailgate shall be the same as the side
panels. The tailgate degree of travel shall be not less than 10 degrees and not more than
15 degrees below horizontal measured to the face of the tailgate and without chains. The tailgate
shall accept a rolling load equal to the specified payload without evidence of deformation or
permanent set. The tailgate shall be so constructed that the approach ramp shall be not more than
0.375 inch above the ground surface. The tailgate shall have a ramp angle of 10 degrees, plus or
minus 1 degree, below the longitudinal plane of the trailer body floor. The tailgate shall be
provided with a latch and corrosion resistant safety chains covered with a heavy protective boot.
Chains shall be of a length to support the tailgate in horizontal position.