Caster, Camber And Toe-In; Front Alignment Requirements - Pontiac TRANS AM 1977 Service Manual

3A-2 1977 PONTIAC SERVICE MANUAL
5
OF VEHICLE OF WHEEL OF WHEEL
I I
4
+POSITIVE
DIRECTION
CAMBER ANGLE
FRONT VlEW
BALL
AXIS
POSITIVE
DIRECTION
CASTER ANGLE
SIDE VlEW
I
WHEEL TOE-IN
I
TOP VIEW
FIG.3A-1 CASTER, CAMBER AND TOE-IN
FRONT ALIGNMENT REQUIREMENTS
4. Check for run-out of wheels and tires.
5. Check vehicle trim heights; if out of limits and a
correction is to be made, the correction must be made before
adjusting caster, camber or toe-in.
NOTE: Good judgement should be exercised before
replacing a spring when vehicle trim height is only
slightly out of limits
(+
3/4").
6. Check for steering gear looseness at frame.
7. Check for improperly operating shock absorbers.
8. Check for loose control arms.
9. Check for loose or missing stabilizer bar attachments.
10. Consideration must be given to excess loads, such as
tool boxes. If this excess load is normally carried in the
vehicle it should remain in the vehicle during alignment
checks.
11. Consider the condition of the equipment being used
to check alignment and follow the manufacturer's
instructions.
12. Regardless of equipment used to check alignment,
the vehicle must be on a level surface both fore and aft and
transversely.
Satisfactory vehicle operation may occur over a wide
range of front suspension alignment settings. Nevertheless,
should settings vary beyond certain tolerances, readjustment
of alignment is advisable. The specifications stated in column
1 of Fig. 3A-11 should be used by owners, dealers and
repairmen as guidelines in vehicle diagnosis either for repairs
under the new vehicle warranty or for maintenance service
at customer's request. These specifications provide an
acceptable all around operating range in that they prevent
abnormal tire wear caused by wheel alignment.
Governmental Periodic Motor Vehicle Inspection
programs usually include wheel alignment among items that
are inspected. To provide useful information for such
inspections, the specifications stated in column 2 of Fig. 3A-
11 are given and these are well within the range of safe vehicle
operation.
In the event the actual settings are beyond the
specifications set forth in column 1 or 2 (whichever is
applicable), or whenever for other reasons the alignment is
being reset, the recommended specifications in column 3 of
Fig. 3A-11 should be used.