Pinion And Ring Gear; Bearings - GMC T Series 1994 Repair Manual

Figure 7— Removing the Pinion Flange
• Thrust washers for wear.
• The fit of the side gears in the differential case.
• The fit of the side gears on the axle shafts.
• Differential case for cracks and scoring.
• Replace all worn parts.

PINION AND RING GEAR

Inspect
L*
• Pinion and ring gear teeth for cracking, chipping,
scoring, or excessive wear.
• Pinion gear splines for wear.
• Pinion flange splines for wear.
• The fit of the pinion gear on the pinion flange.
• The sealing surface of the pinion flange for nicks,
burrs, or rough tool marks that would cause dam­
age to the seal's inside diameter and result in an
oil leak.
• Replace all worn or broken parts.
— Ring and pinion gears are matched sets and
both must be replaced any time a replacement
of either is necessary.
Figure 8— Removing the Drive Pinion
Figure 9— Removing the Pinion Rear Bearing
Important
• A new pinion flange must be replaced when
ring gear and pinion gear are replaced to main­
tain proper system balance.

BEARINGS

L *
Inspect
• Bearings visually and by feel.
• The bearings should feel smooth when oiled
and rotated while applying as much hand pres­
sure as possible.
The large end of the bearing rollers for wear. This
is where tapered roller bearing wear is most evi­
dent.
Bearing cups for wear, cracks, brinelling, and scor­
ing.
Bearings and cups are replaced only as sets.
• If the axle was operated for an extended period
of time with very loose bearings, the ring gear
and drive pinion will also require replacement.
• Low mileage bearings may have very small
scratches and pits on the rollers and bearing
cups from the initial preload. Do not replace a
bearing for this reason.
• Bearing caps for cracks or chips.