TRUCK SERVICE MANUAL
Remove all dirt, old lubricant, and gasket material
from components of the rear axle. Immerse in cleaning
solvent and use a stiff brush if necessary. Bearings should be
cleaned separately in clean solvent and special efforts taken
to protect their finely machined surfaces. If compressed air is
used for drying, do not spin bearings while drying.
Examine all bearings for roughness, damage or wear by
rotating each bearing slowly in hand. If in doubt as to bearing
condition, replace. Ring gear, drive pinion, differential pinions
and any other gears should be checked for damaged teeth,
worn spots, or distortion. Inspect differential case assembly
for cracks, damage or distortion. Make sure splined ends of
axle shafts are neither twisted nor cracked. Shim packs
should be of uniform thickness. Discard thrust washers and
obtain new, even when only slight wear is indicated. Always
use new gaskets.
accomplished in the reverse order of the disassembly. There
are, however, various adjustments which must be secured as
the assembly progresses. In addition to the adjustments there
are also a few precautions to be observed. Among these are
reassembling the pinion cage.
If the ring gear was removed from the differential
case half, be sure correct rivet pressures are used in
reinstalling gear to case.
Prelubricate all parts of the differential assembly
before bolting case halves together.
When installing differential bearing caps, make sure
they are correctly aligned and that the bearing cups
fit properly. If the bearing caps do not seat easily,
the adjusting nuts may be cross threaded. Forcing
caps into place will cause irreparable damage to the
differential carrier or bearing caps.
Observe torque settings from specifications when
tightening any parts.
When making axle repairs such as bearing or drive
gear replacement, or when simply making an adjustment, it is
most important that the ring gear and pinion be positioned
correctly to obtain proper tooth contact. Once the adjustment
is obtained, quiet and durable performance from the rear axle
Fundamentally, the correct tooth contact is obtained
by moving the pinion toward or away from the ring gear as
necessary, or by moving the ring gear toward or away from
the pinion. The actual procedure has been reduced to five
principal steps. Each step is vitally important to axle life and
satisfactory performance, and for that reason, each step is
covered more fully in succeeding paragraphs. The five steps
and the order in which they should be performed are as
Preload pinion bearings in pinion cage. This is
determined by the thickness of spacer between the
two pinion thrust bearings, Fig. 18.
Establish pinion nominal dimension , Fig. 1. Use
the SE1065 Pinion Setting Gauge and add or remove
shims to obtain this dimension.
Set gear lash between ring gear and pinion. Do this
by moving the ring gear to or from the pinion by
means of bearing adjusting nuts, Fig. 9.
accomplished by tightening bearing adjusting nuts,
Check gear tooth contact. Use the paint
impression method for this.
PRELOAD PINION BEARINGS
Before the pinion and drive gear can be adjusted for
correct tooth contact, the pinion bearing preload must be set.
Preloading the pinion bearings is accomplished by selecting
the correct size spacer, Fig. 18, located between the two
pinion thrust bearings, and tightening pinion end nut to the
Temporarily bolt up the pinion, cage and flange
assembly, less oil seal and retainer, and clamp the assembly
in a vise so as to hold the companion flange, Fig. 17. Pinion
end nut should then be drawn tight to the torque shown in
specifications. The applying of correct torque to the various
pinion end nuts, etc. usually calls for torque limits beyond the
capacity of the ordinary torque wrench. Where this is the
case, the chart listed below may be used as a guide for
obtaining the torque required. Fig. 20 illustrates the length of
the wrench handle (A) and the effort that must be applied at
(B) when tightening to secure the necessary torque.
The cage should be rotated while tightening the
pinion end nut in order to seat and align the bearings. The
rotation of the pinion bearings is important; otherwise, a false
condition of bearing load could exist. The bearing rollers
CTS-2095S-CHAPTER I-Page 9
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