Transmission
DODGE
Turbo Diesel
Automatic
Transmission
Page 21-3
Automatic
Transmission
Chrysler
A727 three speed
(Modified
for Dodge Ram/Cummins Turbo
5.9
Liter Engine)
The Loadflite A727 (Diesel Option) is designed
with
a
new
case,
larger capacity
front
pump and Borg Warner
[12.2
inch]
torque converter. The transmission is designed
to be
input torque-limited
at
[400
ft-lb]
with
a
converter stall
speed
of
1775 RPM.
The Borg Warner Torque Converter
is
a
nonlockup converter.
Transmission
Ratios
1st
2:45
2nd
1:45
3rd
1:00
Rear
Axle Ratio Front Aide Ratio
3.07:1
(Dana
-
71)
3.07:1
(Dana
-
61)
Throttle Linkage
The
throttle
cable adjustment Is very
important
to
proper
transmission
operation. This adjustment positions
a
valve
which controls shift
speed,
shift quality and
part
throttle
downshift sensitivity,
if
the setting
is
too short, early shifts
and slippage between shifts may
occur.
If
the setting
is
too long, shifts may be delayed and
part
throttle
downshifts
may be very
sensitive.
Refer to Throttle Cable Adjustment".
Road Test
Prior
to
performing
a
road test,
be
certain
that
the
fluid
level and condition, and control linkage adjustments have
been checked and approved.
During the road test the
transmission
should be operated in each position
to
check for slipping and any variation
in
shifting.
Note
whether the shifts
are
harsh
or
spongy and check the speeds where
the
upshifts and downshifts
occur.
Observe
closely
for slipping or engine speed flare-up. Slipping or flare-up in any gear usually indicates
clutch,
band,
or overrunning clutch problems.
If
the condition
is
far advanced, and overhaul
will
probably be
necessary
to restore
normal operation.
In most
cases,
the
clutch
or
band
that
is slipping can
be
determined
by
noting the transmission operation in
all
selector
positions and by comparing which internal units are applied in those positions.
By
observing
that
the rear clutch
is
applied in
both
the
"D"
first gear and
"1
*
first, If the
transmission
slips
in
"D"
range
first gear but does
not
slip in
'T
first gear,
the
overrunning clutch must be the unit
that
is slipping. Similarly,
if
the
transmission
slips
in any two forward
gears,
the rear clutch
is
the slipping unit.
Using
the same procedure,
the
rear clutch and
front
clutch are applied in
"D"
third
gear.
If
the
transmission
slips
in
third
gear, either the
front
clutch or the rear clutch Is slipping. By selecting another gear which does not use one
of
those units,
the
unit which is slipping can be determined.
If
the
transmission
also
slips
in
reverse, the
front
clutch is
slipping,
if the
transmission
does not slip in reverse, the rear
clutch
is slipping.
This
process
of
elimination can
be
used
to
detect any unit which
slips
and
to
confirm proper operation
of
good
units.
However, although road test
analysis
can usually diagnose slipping units, the actual
cause
of the malfunction
usually
cannot be decided. Practically any condition can be
caused
by leaking hydraulic
circuits
or sticking
valves.
Therefore,
unless
the condition
is
obvious, like no drive in "D" range first gear only,
the
transmission should
never be
disassembled
until
hydraulic
pressure
tests have been performed.
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