Chevrolet 70 1969 Series, Shop Manual

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FRONT SUSPENSION 3A-2
Vertical
G Caster Angle
King Pin f
£
i i s
H i
.------------------------
L
-------------------------
■ j
FRONT AXLE CASTER
CAMBER AND KING PIN INCLINATION
TOE-IN
B MINUS A ............................ .. ............... Camber (Inches)
C ........................................... Camber (Degrees Positive)
D ...................................... King Pin Inclination (Degrees)
E MINUS F ............... .. .............................. Toe-in (Inches)
G .............................................. Caster (Degrees Positive)
K MINUS L ............................ King Pin Inclination (Inches)
Refer to "Specifications" for correct dimensions.
KING PIN INCLINATION
T -3 0 28
Figure I — Front End Alignment Chart
F R O N T A X L E C A S T E R
Inclination of king pin from the vertical in the
fore and aft direction of the vehicle(see " G ," fig. 1).
KIN G PIN IN C LIN A T ION
The slant of the king pin toward the center of
the vehicle at the top and outward at the bottom
(see " D , " fig. 1).
FRONT END INSPECTION
Before checking front end alignment, the fol­
lowing front end inspection should always be made:
1. Check tires for proper inflation.
N O T E : Rim-to-floor dimension should be the
same at each wheel.
2. Check wheel installation and run-out.
3. Check wheel bearing adjustment.
4. Check steering tie rod and drag link ends
for looseness.
5. Check king pins for looseness.
CHECKING AN D CORRECTING
FRONT WHEEL TOE-IN
Incorrect toe-in results in excessive tire wear
caused by side slippage and also unstable steering
with a tendency to wander. Toe-in maybe measured
from center of tire treads or from inside of tires.
Measurements are made at both front and rear of
axle (see
" E ”
and
" F , "
fig. 1).
When setting "toe-in" adjustment, the front
suspension must be neutralized; that is, all com ­
ponent parts must be in the same relative position
when making the adjustment as they will be when
in operation. To neutralize the suspension, the
vehicle must be rolled forward 12 to 15 feet. By
rolling the vehicle forward, all tolerances in the
front suspension are taken up and the suspension
is then in normal operating position. Neutralizing
the front suspension is extremely important, es­
pecially if the vehicle has been jacked up in order
to scribe the tires, otherwise the front wheels will
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L