Chevrolet 1977 10 Series, Repair Manual, Page: 107 / 468

REAR AXLE DIFFERENTIAL
4B-35
... -.......... :
PROTECTIVE
TUBE OR PIPE
J—8 6 0 9
Fig. 23C—In s ta llin g P inion Rear Bearing
w ith a h am m er and d rift, until oil seal flange seats
ag ain st the carrier.
6. Install com panion flange using H older J-8 6 14-11
a n d Installer J-5780. See F ig u re 24C.
7. Pack the cavity betw een en d o f p in io n splines and
p in io n flange w ith a n o n h a rd e n in g sealer (such as
Perm atex Type A o r eq u iv ale n t) p rio r to in stallin g
w ash er and nut on pin io n .
8. Install a new nut on p in io n sh aft. T ig h ten n u t to
rem ove end play—continue a lte rn a te ly tig h ten in g in
sm all increm ents, and checking p relo ad w ith torque
w rench J-5853 and a d a p te r J-5810 until torque
re q u ired to rotate p in io n is 20-30 in. lbs. fo r new
b earings and seal, or 5-15 in. lbs. w hen used p a rts
are reinstalled. See F ig u re 25C.
CHECKS AND ADJUSTMENTS
F o u r ad ju stm en ts are essential fo r p ro p e r o p eratio n o f
the differential and its re lated p arts. T hese adjustm ents
Fig 24C—Installing Companion Flange
Fig. 25C—M easuring R o ta tin g Torque
are a) Pinion B earing P reload, b) Side B earing Preload,
c) Pinion D ep th a n d d) R ing g e a r-to -P in io n Backlash.
Pinion B earing P reload is set to specifications in step 8
o f "D riv e P in io n —In stallatio n and A d ju stm en t."
Side B earing P reload is set to specifications in step 14 o f
"D ifferen tia l C ase—In sta lla tio n an d A d ju stm en t."
Follow ing service to the D ifferen tial Case or to the D rive
P inion and R ing G e a r, a G e a r T ooth C o n tact P attern
Check
must
be m ade to v erify the accuracy o f the work
in setting the p in io n d ep th and the R in g G e a r-to -P in io n
backlash.
Gear Tooth Contact Pattern Check
P rio r to final assem bly o f the d ifferential, a G e a r T ooth
C ontact P a tte rn Check is necessary to v erify the correct
relatio n sh ip betw een rin g g e a r a n d drive p in io n . G e a r
sets w hich are not p o sitio n ed p ro p e rly m ay be noisy, or
have short life, o r both. W ith a p a tte rn check, the m ost
desireable contact betw een rin g g e a r a n d drive p in io n
fo r low noise level and long life can be assured.
Gear Tooth Nomenclature
T he side o f the rin g g e a r tooth w hich curves outw ard, or
is convex, is re fe rred to as the " d riv e " side. T h e concave
side is the "c o a st" side. T he end o f the to o th n earest
center o f rin g g e ar is re fe rre d to as the " to e " end. The
end o f the tooth fa rth e st aw ay fro m cen ter is the " h e e l"
end. Toe end o f tooth is sm aller th a n heel end. See
F igure 26C.
Test
1. W ipe oil out o f c a rrie r a n d carefu lly clean each
tooth o f ring gear.
2. Use g ear m ark in g co m p o u n d an d apply this
m ixture sparingly to all rin g g ear teeth using a
m edium stiff brush. W h en p ro p e rly used, the area
o f p in io n tooth contact will be visible w hen h an d
load is applied.
J - 5 7 8 0
J—8614-1 1
3. T ighten b earin g cap bolts to 55 lb. ft.