point) and shall be not less than 3/8 inch thick. The plate shall
include a coupling ramp having not less than 1-1/4 inch vertical height.
Unless the coupling ramp is protected by the number 1 crossmember, drain
holes shall be provided to prevent any collection of water. A universal
kingpin conforming to MS53038, MS53039, and MS53040 with SAE J700 and
J848 kingpins, shall be installed not less than 21 inches from the front
of the semitrailer. The kingpin assembly shall permit access to allow
personnel to reverse the kingpin without removal of other assemblies.
22.214.171.124 Rear towing compo nents.
Except as specified herein, towing
components shall be furnished on the rear of the semitrailer in accord-
ance with SE J849, for doubles trailer application, The pintle shall
conform to MS51118.
126.96.36.199 Front and rear intervehicular connections. The semitrailer
shall be furnished with airbrake couplings as specified in 188.8.131.52 and
electrical receptacles specified in 3.13.6 for connecting (1) the truck-
tractor to the semitrailer, (2) the dolly to the semitrailer and (3)
accordance with SAE J702 and the rear with SAE J849, except as speci-
fied herein for military system compatibility. Service brake couplings
shall be on the curb side, color coded blue, and emergency brake coupling
shall be on the road side, color coded red. Clearance about the couplings
and receptacles shall allow operating personnel to connect the truck-
tractor, or dolly hoses and harness to the semitrailer and from the semi-
trailer to the towed dolly or trailer without interference with other
components. The airbrake couplings shall be protected with spring-
loaded dust covers. The front electrical receptacle shall have leads
terminating within a splashproof semitrailer electrical nose box or
junction boxes (see 3.13.6).
3.13.2 Rear suspension. The rear of the semitrailer shall be mounted
on a dual-tire, single or tandem axle assembly. Single axles shall be
of the sprung, cushion, or rigid mount type and tandem axles shall be of
the walking beam type. Each axle shall be rated by the axle manufac-
turer at a commercial highway usage capacity rating of not less than
25,000 pounds, but the load on each axle shall not exceed the limit speci-
fied in 3.1.2(c). Bearing cones, bearings, and bearing cups (see 3.13.3)
shall be furnished by the same bearing manufacturer. The suspension
shall be in correct alinement with the frame and with the axles so that
the diagonal measurements from the center of the kingpin to the outer
center of each spindle on the axle do not differ in excess of 1/8 inch
for every 20 feet or fraction thereof of diagonal distance. Each sub-
sequent axle shall be parallel to the front axle of multiple axle