Cleaning; Inspection - GMC T Series 1994 Repair Manual

Figure 7— Removing the Pinion Flange
Figure 8— Removing the Drive Pinion

CLEANING

Do not steam-clean drive parts that have ground and
polished surfaces such as gears, bearings, and shafts.
All parts should be disassembled before cleaning.
These parts should be cleaned in a suitable solvent.
Parts should be thoroughly dried immediately after
cleaning. Use soft, clean, lintless rags. Parts may be
dried with compressed air. Do not allow the bearings to
spin while drying them with compressed air.
INSPECTIO N
It is critical to carefully and thoroughly inspect all
drive unit parts before reassembly.
Thorough inspection of the drive parts for wear or
stress and subsequent replacement of worn parts will
eliminate costly drive component repair after reassem­
bly.
AXLE HOUSING
Inspect
The carrier bore for nicks or burrs that can prevent
the outer diameter of the pinion seal from sealing.
Remove any that are found.
• The bearing cup bores for nicks or burrs. Remove
any that are found.
• The housing for cracks. Replace the housing if any
are found.
• The housing for foreign material such as metal
chips, dirt, or rust. Refer to " Cleaning."
DIFFERENTIAL
Inspect
C
• Pinion gear shaft for unusual wear.
• Pinion gear and side gear teeth for wear, cracks,
scoring, and spalling.
• 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.
• All parts for wear and replace if necessary .
PINION AND RING GEAR
• Ring and pinion gears are matched sets and both
are replaced any time a replacement of either is
necessary. A new pinion flange must be replaced
when both ring and pinion gear are replaced to
maintain proper system balance.
Inspect
L *
Pinion and ring gear teeth for cracking, chipping,
scoring, or excessive wear.
Pinion splines for wear.
Pinion flange splines for wear.
F4695
The fit of the pinion gear splines on the pinion
flange.
The sealing surface of the pinion flange for nicks,
burrs, or rough tool marks that could cause dam­
age to the seal's inside diameter and result in an
oil leak.
All worn or broken parts and replace if necessary.
BEARINGS
Inspect
Bearings for smooth rotation after oiling them.
Bearing rollers for wear.
Bearing cups for wear, cracks, brinelling, and scor­
ing.
Important
When replacing worn or cracked bearings and
cups, be sure to replace them in sets.
Ring gear and pinion gear for wear. If worn,
replace them as a set.
Important
• Low m ileage bearings m ay have very sm all
scratches and pits on the rollers and the bearing
cups from the initial preload. Do not replace a
bearing for this reason.