Chevrolet 70 1969 Series, Shop Manual

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TRANSMISSION AND CLUTCH 7-14
f i g u r e 1 8 — In s ta llin g T ra n s m is s io n C o n tro l C o v e r
gaskets (60), so retainer (61) will limit fore and aft
movement of bearing to m axim um of 0.015-inch. Re­
tainer (61) must contact gasket (60) firmly to prevent
lubricant leakage. Tighten attaching bolts (62) secure­
ly.
5. At rear end of transmission install mainshaft rear
bearing (48), driving bearing inner race onto main­
shaft (31) at same time bearing outer race is driven
into transmission case (77). Install speedometer drive
gear (47) on mainshaft (31).
6. Install mainshaft rear bearing retainer (45) and new
gasket (46). Tighten attaching screws (86) firmly.
7. Install flange (43) with propeller shaft brake drum (if
used) on mainshaft (31). Install flange nut (42). Tight­
en nut to 125 foot-pounds torque minimum. Secure
flange nut (42) with new cotter pin.
8. Install parking brake parts (if used) and adjust park­
ing brake.
CH ECKIN G 4TH AND 5TH SPEED
SYNCHRONIZER FLOAT
Key numbers in text refer to Figure 3.
After bearing retainers and flange nut have been in­
stalled and tightened, check float or fore and aft move­
ment at 4th and 5th speed synchronizer assembly as fol­
lows:
1. Press front (4) and rear (8) outer stop rings solidly
toward 4th and 5th speed sliding clutch (6); then push
the complete synchronizer assembly toward the rear
as far as possible.
2. Using two equal sets of feeler gauges, one on each
side of mainshaft (31), measure space between rear
face of synchronizer rear outer stop ring (8) and
mainshaft 4th speed gear (10). Space measured should
be 0.050 inch to 0.070 inch for proper operation of
the transmission.
3. If 4th and 5th speed synchronizer has too much clear­
ance, remove mainshaft and add 4th speed gear shims
(9) as shown in Figure 16 as necessary to reduce
clearance. Remove shims if necessary to increase
clearance. Shims are available in two thicknesses for
this purpose.
INSTALLATION OF TRANSMISSION
CONTROL COVER
Key numbers in text refer to Figure 3.
1. Place transmission in 2nd gear. Rotate 2nd and 3rd
speed synchronizer parts until pins on inner rings (49
and 51) are aligned and partially engage 1st speed
gear (40).
2. Move reverse idler gear assembly forward; then posi­
tion control cover (21) and new gasket (22) above
transmission case (77) (fig. 18).
3. Carefully lower control cover (21) and gasket (22)
into position on case (77) while guiding reverse shift
fork (38), through relieved area in transmission case,
past synchronizer pins (fig. 18).
NOTE: At this point it m ay be necessary to
move the 1st speed sliding gear (40) slightly
forward (using a screwdriver) to enable 1st
speed shift fork (23) to properly engage groove
of gear (40).
4. Install two dowel bolts and lock washers and tighten
finger-tight. Install remaining attaching bolts. Tighten
all bolts firmly.
5. On transmissions equipped with remote controls, in­
stall remote control assembly and new gasket on
transmission control cover. Tighten attaching bolts se­
curely.
SPECIFICATIONS
GENERAL DATA
M ake........................................................................ New Process
Type.......................................................................... Synchromesh
Direct Drive Models............. 540GD;540GL;541GL;541GD
GEAR RATIOS
Speeds
541GL
541GD
1 st Speed.......................... ........................7.24 to 1
6.15 to 1
2nd Speed ........................ ........................3.88 to 1
3.30 to 1
3rd Speed........................ ........................2.19 to 1
1.86 to 1
4th Speed........................ ........................ 1.37 to 1 1.17 to 1
5th Speed........................ ........................ 1.00 to 1 1.00 to 1
Reverse............................. ........................7.22 to 1 6.13 to 1
MAINSHAFT
Dia. of Pilot E nd.....................................................0.9835” - 0.9839”
Dia. at 2nd Speed G ear........................................1.7490” - 1.7495”
Dia. at 3rd Speed G ear......................................... 2.1245” - 2.1250”
Dia. at 4th Speed G ear..........................................2.1240” - 2.1245”
Dia. at Rear Bearing Surface.............................1.5743” - 1.5748”
COUNTERSHAFT
Dia. at Front Bearing Surface.............................1.3775” - 1.3780”
Dia. at Rear Bearing Surface...............................1.7485” - 1.7500”
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L