Dodge RAM TRUCK 1500 1995 Service Manual page 1402

@R — _ _ _ _ _ _ 42RH/46RH/47RH TRANSMISSION DIAGNOSIS AND TESTING 21 -119
TRANSMISSION DIAGNOSIS
C O N D I T I O N
P O S S I B L E C A U S E S
CORRECTION
NO DRIVE RANGE
(REVERSE OK) - CONT.
5. Transmission overrunning
clutch failure.
6. Input shaft seal rings worn or
damaged.
5. Remove and disassemble transmission;
replace overrunning clutch.
6. Remove and disassemble transmission;
replace seal rings and any other worn or
damaged parts.
NO DRIVE OR REVERSE
(VEHICLE) WILL NOT
MOVE
1. Low fluid level.
2. Gearshift cable or linkage loose,
damaged, or misassembled.
3. Failure of driveline component,
such as U-joint, axle shaft,
case component, etc.
4. Low fluid pressure due to worn
or damaged oil pump.
5. Transmission internal
component damaged.
6. Valve body malfunction (seized
• valve, damaged manual lever,
valve body screws loose or
overtightened causing distortion
and bind).
1 . Add fluid and check for leaks if drive
is restored.
2. Adjust, and reassemble linkage
as needed; replace worn, damaged cable.
3. Perform preliminary inspection procedure
for vehicle that will not move; refer to
procedure in diagnosis section.
4. Perform pressure test to confirm low
pressure; replace pump body and/or gears
if necessary.
5. Remove and disassemble transmission;
repair or replace failed components as
needed.
6. Remove, disassemble, and inspect valve
body; replace valve body (as assembly)
if any valve or bore is damaged; clean and
reassemble correctly if all parts are in good
condition.
MOVES IN 2ND OR 3RD
GEAR, ABRUPTLY
DOWNSHIFTS TO LOW
1 . Governor valve sticking.
2. Valve body malfunction.
1 . Remove, clean, and inspect; replace
faulty parts.
2. Remove, clean, and inspect; look for
stuck 1 -2 valve or governor plug.
SLIPS IN LOW GEAR ONLY,
BUT NOT IN 1 POSITION
1 . Overrunning clutch faulty, not
holding.
1 . Replace overrunning clutch.
SLIPS IN FORWARD DRIVE
RANGES .
1 . Low fluid level.
2. Air in fluid (fluid is foamy, full
of bubbles), shifts are spongy,
caused by air getting into pump
suction passages.
3. Gearshift or throttle linkage/cable
out of adjustment.
4. Low hydraulic pressures due to
worn pump, incorrect control
pressure adjustments, valve body
warpage or malfunction, sticking
governor, leaking seal rings, clutch
seals leaking, servo leaks,
clogged filter, or cooler lines.
5. Accumulator piston cracked,
spring broken or seal worn.
6. Clutch or servo malfunction,
leaking seal or worn plates.
7. Overrunning clutch worn, not
holding (slips in 1 only).
1 . Add fluid and check for leaks.
2. Check for bad pump gasket or seals,
dirt between pump halves, and loose pump
bolts or defective O-ring at filler tube.
3. Adjust linkage/cable.
4. Perform hydraulic and air pressure tests
to determine cause.
5. Inspect and repair as necessary.
6. Air pressure check clutch-servo operation
and repair as required.
7. Replace clutch.
J 9 5 2 1 - 1 3 4