Chevrolet 70 1969 Series, Shop Manual

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REAR AXLE 4-49
3. If new cups are to be installed, press cups firmly
against shoulder of pinion cage.
4. Lubricate bearings with recom m ended axle lubricant;
then insert pinion and bearing assembly into cage.
Place original spacer or spacer com bination over pi­
nion shaft.
5. Press outer pinion bearing onto pinion.
6. A djust pinion bearing pre-load as instructed under
“ Pinion Bearing A djustm ent” in “ G E N E R A L R E A R
A X L E I N F O R M A T I O N .”
7. Install oil seal assem bly into retainer.
8. Install new gasket then oil seal retainer and seal as­
sembly on cage. Install shaft yoke on pinion shaft. In­
stall washer and pinion nut, then tighten to recom ­
m ended torque. Insert cotter pin. D o not back off nut
to align cotter pin hole.
PINION CAG E INSTALLATION
(REARWARD AXLE)
1. Install original shim pack on carrier.
2. Position pinion and cage assem bly on carrier housing
bolt holes. Be sure oil passages in shims and cage
index with sim ilar passages in carrier.
3. Install bolts and ock washers. Tighten bolts to cor­
rect torque.
IMPORTANT: If the gauge method is to be used
to determine pinion cage shim pack thickness,
the gauging operation should be accomplished
at this stage of assembly. Refer to "Gear Back­
lash and Tooth Contact" in "GENERAL REAR
AXLE INFORMATION" section. If gauge method
is not to be used, continue with assembly oper­
ations as described in following paragraphs.
DIFFERENTIAL ASSEMBLY
W henever inspection shows that drive gear m ust be re­
placed, it is also necessary to install new pinion as these
parts are serviced in m atched sets.
1. Lubricate differential case inner walls and all the
com ponent parts with recom m ended axle lubricant.
2. Install differential side bearings using an arbor press
or a suitable driver.
3. Position new thrust washer and side gear in bevel gear
half of case. Install spider with pinions in position,
using all new thrust washers. Install rem aining side
gear and new thrust washer (fig. 15).
4. Install other half of case over assembly. Align m ating
m arks on differential case halves (fig. 15). Install four
bolts holding tw o halves of case together. D raw the
two halves together firmly. Check assembly for free
rotation of gears; then install rem aining bolts. T igh­
ten to correct torque then install lock wire.
DIFFERENTIAL INSTALLATION
Proper bearing cup and adjusting ring fit is of utm ost
im portance and should be carefully checked before differ­
ential is installed.
1. T em porarily install bearing cup, adjuster ring, and
bearing cap, then install and tighten cap screws to re­
com m ended torque.
2. Bearing cup m ust be a hand push fit (fig. 21) in bore,
otherwise the bore m ust be reworked w ith a scraper
or em ery cloth, until proper fit is obtained. Location
of high spots in carrier bore can be readily located by
applying a light coating of prussian blue to bearing
cup.
3. If adjusting ring cannot be turned by hand or with a
m axim um of 20 foot-pounds torque, this indicates
that ring m ay be oversize and another ring which pro­
vides proper fit should be used.
4. C oat differential side bearing cones and cups with
rear axle lubricant specified in L U B R IC A T IO N
(SEC. 0) of this m anual.
5. Place bearing cups over bearing cones, then position
differential assem bly in differential carrier.
6. Insert bearing adjusting rings and turn hand tight
against bearing cups.
7. Place differential bearing caps in position on carrier
legs with alignm ent m arks (fig. 22) in line; then tap
lightly into position.
C AU TIO N : If bearing
cap s
do not seat easily
an d properly, adjusting rings m ay be cross­
th rea ded . Rem ove bearin g caps a n d reposition
adjusting rings. Forcing caps into position will
result in irreparable d a m a g e to d iffe ren tia l car­
rier or to bearing caps.
8. Install cap screws, then tighten to recom m ended to r­
que.
9. Tighten adjusting rings alternately until tight. Revolve
differential assem bly after each tightening to assure
norm al bearing contact and to keep bearing cups
straight in bores.
Figure 2 3 — D ifferen tial B e a r in g Pre-Load C h e ck
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SH O P M A N U A L