Peterbilt 325 2017, Operator'S Manual, Page: 355 / 392

TIRES AND WHEEL
1
TREAD
CONTACT WITH
ROAD
Proper-Inflation:
the correct profile
for full contact with
the road.
2
TREAD
CONTACT WITH
ROAD
Under-Inflation:
causes abnormal
tire deflection, which
builds up excessive
heat, running the
risk of failure. It
also causes irregular
wear.
3
TREAD CONTACT
WITH ROAD
Over-Inflation:
reduces the tread
contact area with
the road surface,
concentrating all of
the vehicle weight
on the center of the
tread. This causes
premature wear of
the tire.
Overloaded Tires
Overloading your truck is as damaging
to your tires as underinflation. The
following chart shows how neglect or
deliberate abuse can affect the life of
your tires.
EFFECT OF LOAD PRESSURE ON TIRE LIFE
Vehicle Load Normal 20% Over 40% Over 60% Over 80% Over 100% Over
Tire Pressure Normal 20% Low 30% Low 35% Low 45% Low 55% Low
Expected Total
Tire Mileage
Normal 70% 50% 40% 30% 25%
(03/17) Y53-6060-1C1
5-145
5