Front Wheel Alignment; General Alignment Information; Wheel Alignment Measurements - Dodge D150 1990 Service Manual

• FRONT SUSPENSION 2 - 3
FRONT WHEEL ALIGNMENT
INDEX
Page
General Alignment Information . 3
Pre-Alignment Inspection 4
GENERAL ALIGNMENT INFORMATION
F r o n t wheel a l i g n m e n t involves t h e correct adjust-
ment or positioning o f a l l the i n t e r r e l a t e d suspension
angles and l i n e a r distances t h a t affect the r o t a t i o n
and the steering o f the vehicle f r o n t wheels. The i m -
portance of front wheel a l i g n m e n t a n d wheel/tire bal-
ancing is essential t o m a i n t a i n ease o f steering, good
directional s t a b i l i t y and t o prevent a b n o r m a l t i r e
tread wear.
R o u t i n e i n s p e c t i o n o f t h e f r o n t s u s p e n s i o n sys-
t e m a n d t h e s t e e r i n g c o m p o n e n t s i s a g o o d p r e -
v e n t a t i v e m a i n t e n a n c e p r a c t i c e a n d also h e l p s t o
e n s u r e safe o p e r a t i o n o f t h e v e h i c l e .
The method o f measuring the f r o n t wheel a l i g n -
ment w i l l vary depending on the type of a l i g n m e n t
equipment being used. The i n s t r u c t i o n s provided b y
the manufacturer of the equipment should always be
followed, w i t h the exception t h a t t h e a l i g n m e n t spec-
ifications contained i n t h i s m a n u a l (or a subsequent
service b u l l e t i n ) should always have precedence.
There are six suspension system a n d steering l i n k -
age measurements t h a t are used t o determine i f the
front wheel a l i g n m e n t is correct (Fig. 1):
• vehicle height,
• caster angle,
• camber angle,
• wheel "toe" position,
• steering axis i n c l i n a t i o n , and
• wheel "toe-out" on t u r n s ( t u r n i n g radius).
A l l the angles a n d linear distances are mechani-
cally adjustable except the vehicle height, the steer-
i n g axis i n c l i n a t i o n and the wheel "toe-out" position
on turns ( t u r n i n g radius). A l t h o u g h not adjustable,
the measurements are valuable i n d e t e r m i n i n g i f
there are bent or damaged components involved, par-
t i c u l a r l y w h e n the camber and the caster angles can-
not be adjusted t o be w i t h i n t h e recommended
specifications.
D o n o t a t t e m p t t o m o d i f y a n y s u s p e n s i o n o r
s t e e r i n g c o m p o n e n t b y h e a t i n g a n d b e n d i n g i t .
Page
Wheel Alignment Measurements/Adjustments . . . . . 6
HEIGH"
A 1
r
TOE-IN J
POSITIVE NEGATIVE
CASTER CASTER
FRONT OF VEHICLE
STEERING AXIS INCLINATION
P I V O T ^ ^ ^ ^ ^ ^
POSITIVE NEGATIVE
CAMBER CAMBER
" I
Q
M
TOE-OUT ON TURNS
--^
WHEELS TURN
\ A B O U T COMMON
\ ^ CENTER
X
RN1047
Fig. 1 Wheel Alignment Measurements
The measurements a n d adjustments should be
made i n the following sequence:
• vehicle h e i g h t differential (not adjustable),
• caster angle,
• camber angle (adjustable for 2 W D vehicles only),
• wheel "toe" position,
• steering axis i n c l i n a t i o n (not adjustable), and
• wheel "toe-out" on t u r n s (not adjustable).
The h e i g h t d i f f e r e n t i a l between the left side and
the r i g h t side o f the vehicle should be zero. The ve-
hicle should be on a level surface, or on an a l i g n m e n t
rack, w i t h a f u l l t a n k o f fuel and no luggage or pas-
senger load. The tires m u s t a l l have the same recom-
mended pressure.