MOUNTING AS 3990934 - Caterpillar

Steering Knuckle Adjustment
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(1) Shims (2) GapNote: The end play must be checked at the upper knuckle. If the wheel is removed, use a jack to force the complete knuckle assembly to the maximum upward movement.Refer to the complete procedure in the Disassembly and Assembly module for the power train in order to correctly size the shim packs. Note: Adjustment of the steering knuckle is accomplished by the use of shims (1) that are located between the mounting flanges of the upper and the lower kingpin cap and the steering knuckle. The correct amount of end play is 0.13 to 0.33 mm (0.005 to 0.013 inch).
The vertical end play of the steering knuckle can be measured by using a feeler gauge or a dial indicator. Use a feeler gauge to measure gap (2) that is between the shoulder of the upper kingpin cap and the top surface of the trunnion socket kingpin boss. Use a dial indicator to check the actual vertical movement of the knuckle.Note: The following steps are for the measurement with the feeler gauge.
If the wheels are on the ground and supporting the weight of the machine, the measurement of the gap can be made. Record the measurement.
If the axle is supported on blocks, the knuckle must be forced to the maximum upward movement with a jack or a pry bar before the gap measurement is made. Record the measurement.Note: The following steps are for the measurement with the dial indicator.
If wheels are on the ground and supporting the weight of the machine, zero the dial indicator and jack up the axle until the wheel is off the ground. Record the dial indicator reading of the vertical movement.
If the axle is supported on blocks, zero the dial indicator. Then force the knuckle to the maximum upward movement with a jack or a pry bar. Record the dial indicator reading of the vertical movement.
If the end play is less than 0.33 mm (0.013 inch), no adjustment is necessary.
If the end play exceeds 0.33 mm (0.013 inch), continue with the following steps.
Remove the upper and the lower kingpin caps and measure the total current shim pack thickness (upper pack plus the lower pack).
Subtract actual end play (value from step 1) from the total shim pack thickness (value from step 4) and divide the result by two.
Make a lower shim pack thickness that is identical to the value that was calculated in Step 5. If this thickness cannot be met exactly, choose the nearest thicker shim.
Make a upper shim pack thickness that is identical to the value that was calculated from Step 5 plus 0.13 mm (0.005 inch). If this result cannot be met exactly, choose the nearest thicker shim.Steering Alignment and Steering Stops
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Steering Axle (1) Left and right tie rod yokes (2) Left and right steering stopsSteering Alignment
Measure dimension (A) and (B). Compare the dimensions. The steering alignment is correct when dimension (A) is less than dimension (B) by 0 to 3.20 mm (0 to