Front Caster and Camber Adjustment

IMPORTANT: Caster measurements or valves must be compensated for the measured frame angle.

Caster is relative to frame, the caster values must be compensated for the measured frame angle by using a digital protractor or equivalent on a flat portion of the frame in front of the rear tire.

Fig 1: Identifying Positive Frame Angle

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Frame angle is positive when higher in the rear. Measure both sides of the frame and take an average from those measurements. Then add the average frame angle to the caster reading when making adjustments.

Fig 2: Identifying Negative Frame Angle

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Frame angle is negative when lower in the rear. Measure both sides of the frame and take an average from the measurements. Then subtract the average frame angle from the caster reading when making adjustments.
The caster and camber adjustments are made by rotating the offset cam bolt and the cam in the slotted frame bracket in order to reposition the control arm.
IMPORTANT: Before adjusting the caster and camber angles, jounce the front bumper three times to allow the vehicle to return to normal height.
Measure and adjust the caster and the camber with the vehicle at curb height. The front suspension Z dimension is indicated in Trim Heights. Refer to Trim Height Specifications in Suspension General Diagnosis.

For an accurate reading, do not push or pull on the tires during the alignment process.

Fig 3: Determining The Caster Angle

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Determine the caster angle (2). Be sure to compensate for frame angle where required.

Fig 4: Determining The Positive Camber Or Negative Camber

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Determine the positive camber (2) or negative camber (3) angle.
Remove the pinned adjusting cam insert. Do not reinstall the cam insert.
Loosen the upper control arm cam adjustment bolts.
NOTE: Refer to Fastener Notice in Cautions and Notices.

Fig 5: Adjusting The Caster And The Camber Angle

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Adjust the caster and the camber angle by turning the cam bolts until the specifications have been met.
When the adjustments are complete, hold the cam bolt head in order to ensure the cam bolt position does not change while tightening the nut.

Tighten: Tighten the cam nuts to 190 N.m (140 lb ft).
Verify that the caster and the camber are still within specifications. Refer to Wheel Alignment Specifications .
When the caster and camber are within specifications, adjust the toe. Refer to Front Toe Adjustment .