Chevrolet 70 1969 Series, Shop Manual

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TRANSMISSION AND CLUTCH 7-107
AUXILIARY TRANSMISSION
4-SPEED—MODEL 7041)
Available as an option on Chevrolet 70-80 Series T ruck
models is a S p icer/D an a 4-speed auxiliary transm ission
Series 7041. The 7041 transm ission is similar in design to
the S p icer/D an a 6041 Series auxiliary that is available as
an option on Chevrolet 70-80 Series T ruck models, how ­
ever, these two transm issions differ in ratios, input capac­
ity, and shifter m echanism design.
To accom m odate the higher operating torques of the
6V53 Diesel engine, the larger, higher capacity
7041 Series has heavier com ponents used throughout
the gear train. R atios of the 7041 auxiliary transmission
are as follows:
First ................................................................................ 2.31:1
S e c o n d ............................................................................1.21:1
Third (Direct) ...........................................................1.00:1
Fourth (Overdrive) .................................................0.83:1
OVERHAUL
SHIFT CONTROLS
DISASSEMBLY (Figure 1)
1. Remove retaining capscrews, lock nuts and lock
washers. Separate cover (1) from case and gasket.
2. Remove the two poppet retainers (2) from side of case
and use small m agnet to remove poppet balls (4) and
poppet springs (2).
3. C ut lock wire and remove set screws (5) from 3rd-4th
speed shift fork (6), and lst-2nd speed shift fork (7).
4. Use soft lod to tap (upper) 3rd-4th shift rod (8) and
(lower) lst-2nd shift, rod (9) free of shift forks and out
of case.
NOTE: Use caution as shift rod (9) is removed
from case to prevent loss of shift rod interlock
(ID-
5. If shift rod oil seals (10) are dam aged, pry out with
large screwdriver and discard.
F ig u re 1— A u x ilia r y T ra n sm issio n Shift C o n tro ls a n d C o v e r
1. Transmission Cover
2. Poppet Retainers
3. Poppet Springs
4. Poppet Balls
5. Shifter Fork Lock Screws 9. 1-2 Shift Rod
6. 3-4 Shifter Fork 10. Shift Rod Seals
7. 1-2 Shifter Fork 11. Shift Rod Interlock
8. 3-4 Shift Rod
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L