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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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Troubleshooting
