Chevrolet 1988 Light Duty Truck Repair Manual page 161

• Service shims are available from 0.040 to 0.100-inch.
• Be sure that the side bearing surfaces are clean and
free of burrs.
Tool Required:
J 22779 Side Bearing Backlash Gage
1. Place the differential case and the bearing cups into
the axle housing.
• L u b ric a te th e a x le
lubricant.
• Support the case to keep it from falling into the
axle housing.
2. Install the strap from J 22779 on the left bearing with
the cap bolts. Tighten the bolts snugly.
3. Push the ring gear towards the pinion.
• Engage the ring gear with the pinion tightly, to
a backlash of 0.000 to 0.001-inch.
4. Insert J 22779 between the axle housing and the left
bearing cup (figure 20).
5. Move the tool back and forth in the bore while
tu rn in g th e a d ju s tin g nut to the rig h t u n til a
noticeable drag is produced (figure 21).
• Tighten the lock bolt on the side of the tool.
Figure 20— Installing Side Bearing Gaging Tool
b e a rin g s w ith a x le
1/2-INCH RING GEAR 4B2-9
8
Figure 21— Measuring Side Bearing Shim
Requirem ents
• Leave the tool in place.
6. Install a service spacer (9) and a service shim (9)
between the right bearing cup and the axle housing.
7. D e te rm in e b e a rin g
progressively larger feeler gage sizes between the
carrier and the service shim.
• Push the feeler gage downward so that it
contacts the shim at the top and bottom, and
then contacts the axle housing.
• The point just before additional drag begins is
the correct feeler gage thickness. This is the
zero setting w ithout preload.
8. Remove the strap, J 22779, the service spacer,
service shim, feeler gage, and differential case from
the axle housing.
9. M e a s u re J 2 2 7 7 9 in
micrometer. Average the readings (figure 22).
10. Add the dim ensions of the right side service spacer,
service shim, and the feeler gage.
Figure 22— Measuring the Gage Plate Thickness
p re lo a d by in s e r tin g
th re e p la c e s u s in g a