Diagnostic Procedure # 2 - Alignment
Wheel Alignment - Measure the front wheel alignment. For out of specification vehicles, align to the "1991 Preferred Alignment Specifications"
NOTE: F-350 4X4 VEHICLES ARE NOT ALIGNABLE.
^ Spin the front tires to be sure that the front hubs are unlocked, If hubs are unlocked, the axle shaft will not rotate with the wheels (4x4 models only).
^ Do not adjust wheel alignment to correct for brake pull if the vehicle does not have pull during non-brake applications.
^ Set the tire pressure to the specification on the certification label.
Compare the installed tires and wheels to the certification label. If the tires and wheels match, continue with the diagnostic procedure.
^ IF THE TIRES AND WHEELS DO NOT MATCH THE CERTIFICATION LABEL, compare tires and wheel to RPO (regular production option) list and set tire pressure to the correct value.
^ IF THE TIRES AND WHEELS DO NOT MATCH CERTIFICATION LABEL OR RPO AVAILABILITY, swap known good tires and wheels (as called for by the certification table or RPO list) for the purposes of evaluation only.
Drive vehicle after alignment is performed.
1990 PREFERRED ALIGNMENT SPECIFICATIONS
MODEL ALIGNMENT SPECIFICATION
TOE-IN ADJUST
All +.03 +/-.06 Inch Or
+.06 +/-.13~
CASTER SPLIT - LH
CASTER MINUS RH
CASTER (SEE TSB
89-21-10)
Bronco, F-Series 0 +/- .50~-.3 +/-
.50~
CAMBER SPLIT - LH
CAMBER MINUS RH
CAMBER
All 0 +/-.50~
AVERAGE CAMBER *
All 0.25 +/-.50~
AVERAGE CASTER **
All Min. 2.00/Max. 6.00~
* Defined as (LH camber + RH camber) divided by
2. Vehicles set to this specification, as measured with the vehicle loaded to normal loading conditions, will result in optimum tire wear.
** Defined as (LH caster + RH caster) divided by
2. These are not recommended values for settings. They are only maximum and minimum limitations.
* Vehicles which exceed the maximum average caster value shown above may result in shimmy concerns.
* Vehicles operated below the minimum average caster value shown may result in wander and poor steering returnability concerns.
NOTE: A VEHICLE WILL PULL TO THE SIDE THAT HAS THE LEAST AMOUNT OF POSITIVE CASTER. THESE SPECIFICATIONS WILL RESULT IN THE RH CASTER BEING SLIGHTLY HIGHER (LEFT IS LOWER). THIS IS DONE TO COMPENSATE FOR ROAD CAMBER.