Aviator 2WD V8-4.6L DOHC (2003)
Pilot Runout
1. Position the special tools on the pilot, as close to the hub as possible. Zero the indicator to allow the pointer to deflect either way.
2. Rotate the hub one full turn and note the maximum and minimum readings. The difference between the maximum and minimum readings will be
the total pilot runout. Pilot runout must not exceed 0.15 mm (0.006 inch).
Wheel Hub Runout
1. Position the special tool on the wheel hub, as close to the outer edge as possible. Zero the indicator to allow the pointer to deflect either way.
2. Rotate the hub one full turn and note the maximum and minimum readings. The difference between the maximum and minimum readings will be
the total wheel hub runout. The runout must not exceed 0.127 mm (0.005 inch).
Drive Pinion Stem and Pinion Flange
Check the pinion flange runout when all other checks have failed to show the cause of the vibration.
One cause of excessive pinion flange runout is incorrect installation of the axle drive pinion seal Check to see if the spring on the seal lip has been
dislodged.
Halfshafts
NOTE: Constant Velocity (CV) joints must not be installed unless disassembly and inspection reveals unusual wear.
NOTE: While inspecting the boots, watch For indentations ("dimples") in the boot convolutions. Indentations must be removed.
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Inspect the boots for evidence of cracks, tears, or splits.
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Inspect the underbody for any indication of grease splatter near the boots outboard and inboard locations. This is an indication of boot/clamp
damage.
Axle Noise
NOTE: Before disassembling the axle to diagnose and correct gear noise, eliminate the tires, exhaust, trim items, roof racks and wheel bearings as
possible causes. Follow the diagnostic procedures.
The noises described as follows usually have specific causes that can be diagnosed by observation as the unit is disassembled. The initial clues are the
type of noise heard during the road test.
Gear Howl and Whine
Howling or whining of the ring gear and pinion is due to an incorrect gear pattern, gear damage or incorrect bearing preload.
