Front Axle

REMOVAL AND INSTALLATION

REMOVAL SERVICE POINT
[A] FRONT PROPELLER SHAFT REMOVAL





Make mating marks on the flange yoke and the differential carrier companion flange. Remove the front propeller shaft.

INSTALLATION SERVICE POINTS
]A[ CLUTCH GEAR BEARING END PLAY INSPECTION
Check the end play of the clutch gear bearing by the following procedure before installing the freewheel clutch assembly.
1. Insert flat washers of the same thickness as the housing tube [9.0 mm (0.35 inch)] onto the bolt, and then temporarily install the freewheel clutch assembly to the front differential.
2. Place a micrometer against the end of the clutch gear and check the end play of the clutch gear bearing.
Standard value: 0.05 - 0.30 mm (0.002 - 0.012 inch)





3. If the play is not within the standard value, disassemble the bearing and insert a spacer of the appropriate thickness.

NOTE: The thicknesses of the spacers vary in steps of 0.25 mm (0.010 inch).

]B[ FRONT PROPELLER SHAFT INSTALLATION
Install the front propeller shaft so that the mating marks of the flange yoke and the differential carrier companion flange are aligned.

]C[ VACUUM HOSE INSTALLATION





Install the vacuum hoses so that they match the identification colors of the actuator assembly nipple.

INSPECTION BEFORE DISASSEMBLY
1. Remove the cover and gasket.





2. Hold special tools MB990909 and MB99116 in a vise, and install the differential carrier assembly to it.

DRIVE GEAR BACKLASH





1. With the drive pinion locked in place, use a dial gauge to measure the drive gear backlash in four or more places on the drive gear.
Standard value: 0.11 - 0.16 mm (0.004 - 0.006 inch)
2. If the backlash is not within the standard value, insert side bearing adjustment spacers, and then inspect the drive gear tooth contact.

DRIVE GEAR RUNOUT





1. Measure the drive gear runout at the shoulder on the reverse side of the drive gear.
Limit: 0.05 mm (0.002 inch)
2. When the runout exceeds the limit value, check for foreign material between drive gear rear side and differential case, and for loose drive gear installation bolts.
3. When check (2) gives normal results, reposition drive gear and differential case and remeasure.
4. If adjustment is impossible, replace differential case, or replace drive gear and pinion as a set.

DIFFERENTIAL GEAR BACKLASH





1. While locking the side gear with the wedge, measure the differential gear backlash with a dial indicator on the pinion gear.
Standard value: 0 - 0.076 mm (0 - 0.0030 inch)
Limit: 0.2 mm (0.01 inch)
Repeat the same procedure for both pinion gears.
2. If the backlash exceeds the limit, adjust by using the side gear thrust spacers.
3. If adjustment is impossible, replace the side gear and pinion gear as a set.

DRIVE GEAR TOOTH CONTACT
Check the tooth contact of drive gear by following the steps.





1. Apply a thin, uniform coat of machine blue to both surfaces of the drive gear teeth.

CAUTION: If the drive gear is rotated too much, the tooth contact pattern will become unclear and difficult to check.





2. Insert special tool MB990939 between the differential carrier and the differential case, and then rotate the companion flange by hand (once in the normal direction, and then once in the reverse direction) while applying a load to the drive gear so that the revolution torque [approximate 2.5 - 3.0 Nm (22.1 - 26.6 inch lbs.)] is applied to the drive pinion.





3. Check the tooth contact condition of the drive gear and drive pinion.

NOTE: Confirm that the pinion height and backlash adjustments have been done properly by inspecting the tooth contact pattern. Continue to adjust the pinion height and backlash until the tooth contact pattern resembles the standard pattern. After adjustments, if the correct tooth contact pattern cannot be obtained, the drive gear and the drive pinion are worn beyond the allowable limit. Replace the gear set.