APPROX. TOTAL WEIGHT DISTRIBUTION-VEHICLE + PAYLOAD
The above diagram shows design of trailers for uniform
load distribution. When loading trucks, design provides for
90% payload on rear tires and 10 % on front tires; when loading
trailers, distribute payload equally between rear tires and fifth
wheel which transfers its load to truck tractor.
Do not load trailer with payload concentrated at front. Such
placement overloads tractor rear tires, reduces tire mileage,
and may bend tractor axle housing. If brakes are applied
suddenly, trailer brakes may lock, causing flat spots on tires
and dangerous skidding.
Distribute load over full length of trailer bed, or place
concentrated load in center of trailer.
Never position payload
as shown at left.
Load on tailgate of
truck 1 and trailer 3
causes severe strain on
frames, axles, tires, and
Overload on rear of
trailer 2, and almost no load
on fifth wheel, permits
truck-tractor drive wheels
to slip, causes excessive
tire wear and uneven
Distribution of Total Weight