Chevrolet LIGHT DUTY TRUCK (SERIES 10-35) Service Manual page 339

3E-2 WHEELS AND TIRES
CAUTION: Servicing of tires mounted on
multi-piece rims requires proper tools,
safety equipment
training. Severe injuries can result from
improper servicing
recommended that tires on multi-piece
rims be serviced only by competent
personnel with proper equipment or by
competent truck tire repair shops.
TIRE INSPECTION AND ROTATION (Fig. 3E-3)
Front and rear tires perform different jobs and can
wear differently depending on the type of roads driven,
individual driving habits, etc. To obtain maximum tire life,
tires should be inspected and rotated regularly (see Section
OB).
For the longest tire life, any time irregular wear is
noticed, the tires should be inspected and rotated and the
cause of the uneven wear corrected. Be certain to check
wheel nut tightness and to adjust the tire pressures, front
and rear, after rotation to agree with those recommended
in the tire inflation charts.
The outer tire on a dual wheel will skid or drag on a
turn because of the difference in the turning radii of the
inner and outer tires. This results in faster wear of the outer
tire. In general, the tire with the largest diameter or least
wear whould be at the outside of each dual wheel. In
addition, when trucks are operated continuously on high
crown roads an increase in air pressure of from 5 to 10 PSI
in the outside tire of each dual produces maximum tire life.
INFLATION PRESSURE
The maximum cold inflation pressures for the factory
installed tires are listed on the Certification Label. Tires
must be inflated to these pressures when the GV W R or an
axle G A W R is reached. Improper tire inflation pressures
for the load the vehicle is carrying can adversely affect tire
life and vehicle performance.
/ M F D . BY G E N E R A L M O TO R S CORP.
08/78
GVWR GAW R FR T
L B /kq 14000/6350 4 0 00/1814
T IR E S 10
1 6 . 5 X 9
R IM S
P SI/kPti [ C O L D D U A L 36/248
[HIS VI H i d [ CONf OHMS 10 A1 f A PR ICABl I HUfc KA| VIU 1 UK V LH IC I E S A K T V SI AM) A KPS
ON T HE DATE M A N U F A C T U R E
C G Q 1691100001
SEE OlA/NkRS M A N U A L FOR A D D IT IO N A L IN F O R M A T IO N
E X A M P L E O N L Y
Fig. 3 E - 1 ~ C e r t i f i c a t i o n La bel
LIG H T T R U CK SER V IC E MANUAL
SERVICE OPERATIONS
and specialized
techniques. It is
~ ~ ' \
GAWR RR
10000 4536
5 X 1 6 5D 10 5 X 1 6 5D
75 16 6 X 9 75
4 2 ' 290
SHOWN ABO VE
BUS -N O T SCHOOL BUS
Too low an air pressure can result in tire overloading,
abnormal tire wear, adverse vehicle handling, and reduced
fuel economy. The tire flexes more and can build up
excessive heat, weakening
susceptibility to damage or failure. Too high an air pressure
can result in abnormal wear, harsh vehicle ride, and
increased susceptibility to damage from road hazards.
Lower inflation pressures should be used only with reduced
vehicle loads and the rear tire pressure should be equal to
or greater than the front pressure on single wheel
application. After determining the load on each tire by
weighing the vehicle on a scale, the correct cold inflation
pressures for the actual tire loads can be obtained from the
Tire/Wheel Load and Inflation Pressure Charts shown in
this section. Refer to Section 0B for additional information
on inflation pressure.
CORRECTING IRREGULAR TIRE WEAR
Heel and Toe Wear
This is a saw-toothed effect where one end of each tread
block is worn more than the other. The end that wears is
the one that first grips the road when the brakes are applied.
Heel and toe wear is less noticeable on rear tires than
on front tires, because the propelling action of the rear
wheels creates a force which tends to wear the opposite end
of the tread blocks. The two forces, propelling and braking,
make for more even wear of the rear tires, whereas only the
braking forces act on the front wheels, and the saw-tooth
effect is more noticeable.
A certain amount of heel and toe wear is normal.
Excessive wear is usually due to high speed driving and
excessive use of brakes. The best remedy, in addition to
cautioning the owner on his driving habits, is to interchange
tires regularly.
the tire and increasing