1998 DODGE RAM 1500 torque

TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
²Leaks at the weld joint around the outside diam-
eter weld.
²Leaks at the converter hub weld.
CONVERTER HOUSING AREA LEAK CORRECTION
(1) Remove converter.
(2) Tighten front band adjusting screw until band
is tight around front clutch retainer. This prevents
front/rear clutches from coming out when oil pump is
removed.
(3) Remove oil pump and remove pump seal.
Inspect pump housing drainback and vent holes for
obstructions. Clear holes with solvent and wire.(4) Inspect pump bushing and converter hub. If
bushing is scored, replace it. If converter hub is
scored, either polish it with crocus cloth or replace
converter.
(5) Install new pump seal, O-ring, and gasket.
Replace oil pump if cracked, porous or damaged in
any way. Be sure to loosen the front band before
installing the oil pump, damage to the oil pump seal
may occur if the band is still tightened to the front
clutch retainer.
(6) Loosen kickdown lever pin access plug three
turns. Apply LoctiteŸ 592, or PermatextNo.2to
plug threads and tighten plug to 17 N´m (150 in. lbs.)
torque.
(7) Adjust front band.
(8) Lubricate pump seal and converter hub with
transmission fluid or petroleum jelly and install con-
verter.
(9) Install transmission and converter housing
dust shield.
(10) Lower vehicle.
DIAGNOSIS AND TESTING - DIAGNOSIS
CHARTS
The diagnosis charts provide additional reference
when diagnosing a transmission fault. The charts
provide general information on a variety of transmis-
sion, overdrive unit and converter clutch fault condi-
tions.
The hydraulic flow charts in the Schematics and
Diagrams section of this group, outline fluid flow and
hydraulic circuitry. Circuit operation is provided for
PARK, NEUTRAL, FIRST, SECOND, THIRD,
FOURTH, MANUAL FIRST, MANUAL SECOND,
and REVERSE gear ranges. Normal working pres-
sures are also supplied for each of the gear ranges.
Fig. 11 Converter Housing Leak Paths
1 - PUMP SEAL
2 - PUMP VENT
3 - PUMP BOLT
4 - PUMP GASKET
5 - CONVERTER HOUSING
6 - CONVERTER
7 - REAR MAIN SEAL LEAK
DRAUTOMATIC TRANSMISSION - 48RE 21 - 145
AUTOMATIC TRANSMISSION - 48RE (Continued)

DIAGNOSIS CHARTS
CONDITION POSSIBLE CAUSES CORRECTION
HARSH ENGAGEMENT
(FROM NEUTRAL TO
DRIVE OR REVERSE)1. Fluid Level Low. 1. Add Fluid
2. Throttle Linkage Mis-adjusted. 2. Adjust linkage - setting may be too long.
3. Mount and Driveline Bolts Loose. 3. Check engine mount, transmission
mount, propeller shaft, rear spring to body
bolts, rear control arms, crossmember and
axle bolt torque. Tighten loose bolts and
replace missing bolts.
4. U-Joint Worn/Broken. 4. Remove propeller shaft and replace
U-Joint.
5. Axle Backlash Incorrect. 5. Check per Service Manual. Correct as
needed.
6. Hydraulic Pressure Incorrect. 6. Check pressure. Remove, overhaul or
adjust valve body as needed.
7. Band Mis-adjusted. 7. Adjust rear band.
8. Valve Body Check Balls Missing. 8. Inspect valve body for proper check ball
installation.
9. Axle Pinion Flange Loose. 9. Replace nut and check pinion threads
before installing new nut. Replace pinion
gear if threads are damaged.
10. Clutch, band or planetary
component damaged.10. Remove, disassemble and repair
transmission as necessary.
11. Converter Clutch Faulty. 11. Replace converter and flush cooler and
line before installing new converter.
21 - 146 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
DELAYED ENGAGEMENT
(FROM NEUTRAL TO
DRIVE OR REVERSE)1. Fluid Level Low. 1. Correct level and check for leaks.
2. Filter Clogged. 2. Change filter.
3. Gearshift Linkage Mis-adjusted. 3. Adjust linkage and repair linkage if worn
or damaged.
4. Torque Converter Drain Back (Oil
drains from torque converter into
transmission sump).4. If vehicle moves normally after 5
seconds after shifting into gear, no repair is
necessary. If longer, inspect pump bushing
for wear. Replace pump house.
5. Rear Band Mis-adjusted. 5. Adjust band.
6. Valve Body Filter Plugged. 6. Replace fluid and filter. If oil pan and old
fluid were full of clutch disc material and/or
metal particles, overhaul will be necessary.
7. Oil Pump Gears Worn/Damaged. 7. Remove transmission and replace oil
pump.
8. Governor Circuit and Solenoid
Valve Electrical Fault.8. Test with DRBTscan tool and repair as
required.
9. Hydraulic Pressure Incorrect. 9. Perform pressure test, remove
transmission and repair as needed.
10. Reaction Shaft Seal Rings
Worn/Broken.10. Remove transmission, remove oil pump
and replace seal rings.
11. Rear Clutch/Input Shaft, Rear
Clutch Seal Rings Damaged.11. Remove and disassemble transmission
and repair as necessary.
12. Regulator Valve Stuck. 12. Clean.
13. Cooler Plugged. 13. Transfer case failure can plug cooler.
NO DRIVE RANGE
(REVERSE OK)1. Fluid Level Low. 1. Add fluid and check for leaks if drive is
restored.
2. Gearshift Linkage/Cable
Loose/Misadjusted.2. Repair or replace linkage components.
3. Rear Clutch Burnt. 3. Remove and disassemble transmission
and rear clutch and seals. Repair/replace
worn or damaged parts as needed.
4. Valve Body Malfunction. 4. Remove and disassemble valve body.
Replace assembly if any valves or bores
are damaged.
5. Transmission Overrunning Clutch
Broken.5. Remove and disassemble transmission.
Replace overrunning clutch.
6. Input Shaft Seal Rings Worn/
Damaged.6. Remove and disassemble transmission.
Replace seal rings and any other worn or
damaged parts.
7. Front Planetary Failed Broken. 7. Remove and repair.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 147
AUTOMATIC TRANSMISSION - 48RE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
NO DRIVE OR REVERSE
(VEHICLE WILL NOT
MOVE)1. Fluid Level Low. 1. Add fluid and check for leaks if drive is
restored.
2. Gearshift Linkage/Cable
Loose/Misadjusted.2. Inspect, adjust and reassemble linkage
as needed. Replace worn/damaged parts.
3. U-Joint/Axle/Transfer Case
Broken.3. Perform preliminary inspection procedure
for vehicle that will not move. Refer to
procedure in diagnosis section.
4. Filter Plugged. 4. Remove and disassemble transmission.
Repair or replace failed components as
needed. Replace filter. If filter and fluid
contained clutch material or metal particles,
an overhaul may be necessary. Perform
lube flow test. Flush oil. Replace cooler as
necessary.
5. Oil Pump Damaged. 5. Perform pressure test to confirm low
pressure. Replace pump body assembly if
necessary.
6. Valve Body Malfunctioned. 6. Check 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.
7. Transmission Internal Component
Damaged.7. Remove and disassemble transmission.
Repair or replace failed components as
needed.
8. Park Sprag not Releasing - Check
Stall Speed, Worn/Damaged/Stuck.8. Remove, disassemble, repair.
9. Torque Converter Damage. 9. Inspect and replace as required.
SHIFTS DELAYED OR
ERRATIC (SHIFTS ALSO
HARSH AT TIMES)1. Fluid Level Low/High. 1. Correct fluid level and check for leaks if
low.
2. Fluid Filter Clogged. 2. Replace filter. If filter and fluid contained
clutch material or metal particles, an
overhaul may be necessary. Perform lube
flow test.
3. Throttle Linkage Mis-adjusted. 3. Adjust linkage as described in service
section.
4. Throttle Linkage Binding. 4. Check cable for binding. Check for return
to closed throttle at transmission.
5. Gearshift Linkage/Cable
Mis-adjusted.5. Adjust linkage/cable as described in
service section.
6. Clutch or Servo Failure. 6. Remove valve body and air test clutch,
and band servo operation. Disassemble
and repair transmission as needed.
7. Governor Circuit Electrical Fault. 7. Test using DRBTscan tool and repair as
required.
8. Front Band Mis-adjusted. 8. Adjust band.
9. Pump Suction Passage Leak. 9. Check for excessive foam on dipstick
after normal driving. Check for loose pump
bolts, defective gasket. Replace pump
assembly if needed.
21 - 148 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
GROWLING, GRATING OR
SCRAPING NOISES1. Drive Plate Broken. 1. Replace.
2. Torque Converter Bolts Hitting
Dust Shield.2. Dust shield bent. Replace or repair.
3. Planetary Gear Set Broken/
Seized.3. Check for debris in oil pan and repair as
required.
4. Overrunning Clutch Worn/Broken. 4. Inspect and check for debris in oil pan.
Repair as required.
5. Oil Pump Components Scored/
Binding.5. Remove, inspect and repair as required.
6. Output Shaft Bearing or Bushing
Damaged.6. Remove, inspect and repair as required.
7. Clutch Operation Faulty. 7. Perform air pressure check and repair as
required.
8. Front and Rear Bands Mis-
adjusted.8. Adjust bands.
DRAGS OR LOCKS UP 1. Fluid Level Low. 1. Check and adjust level.
2. Clutch Dragging/Failed 2. Air pressure check clutch operation and
repair as required.
3. Front or Rear Band Mis-adjusted. 3. Adjust bands.
4. Case Leaks Internally. 4. Check for leakage between passages in
case.
5. Servo Band or Linkage
Malfunction.5. Air pressure check servo operation and
repair as required.
6. Overrunning Clutch Worn. 6. Remove and inspect clutch. Repair as
required.
7. Planetary Gears Broken. 7. Remove, inspect and repair as required
(look for debris in oil pan).
8. Converter Clutch Dragging. 8. Check for plugged cooler. Perform flow
check. Inspect pump for excessive side
clearance. Replace pump as required.
NO 4-3 DOWNSHIFT 1. Circuit Wiring and/or Connectors
Shorted.1. Test wiring and connectors with test lamp
and volt/ohmmeter. Repair wiring as
necessary. Replace connectors and/or
harnesses as required.
2. PCM Malfunction. 2. Check PCM operation with DRBTscan
tool. Replace PCM only if faulty.
3. TPS Malfunction 3. Check TPS with DRBTscan tool at PCM.
4. Lockup Solenoid Not Venting. 4. Remove valve body and replace solenoid
assembly if plugged or shorted.
5. Overdrive Solenoid Not Venting. 5. Remove valve body and replace solenoid
if plugged or shorted.
6. Valve Body Valve Sticking. 6. Repair stuck 3-4 shift valve or lockup
timing valve.
21 - 152 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
SLIPS IN OVERDRIVE
FOURTH GEAR1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Overdrive Clutch Pack Worn. 2. Remove overdrive unit and rebuild clutch
pack.
3. Overdrive Piston Retainer Bleed
Orifice Blown Out.3. Disassemble transmission, remove
retainer and replace orifice.
4. Overdrive Piston or Seal
Malfunction.4. Remove overdrive unit. Replace seals if
worn. Replace piston if damaged. If piston
retainer is damaged, remove and
disassemble the transmission.
5. 3-4 Shift Valve, Timing Valve or
Accumulator Malfunction.5. Remove and overhaul valve body.
Replace accumulator seals. Make sure all
valves operate freely in bores and do not
bind or stick. Make sure valve body screws
are correctly tightened and separator plates
are properly positioned.
6. Overdrive Unit Thrust Bearing
Failure.6. Disassemble overdrive unit and replace
thrust bearing (NO. 1 thrust bearing is
between overdrive piston and clutch hub;
NO. 2 thrust bearing is between the
planetary gear and the direct clutch spring
plate; NO. 3 thrust bearing is between
overrunning clutch hub and output shaft).
7. O/D Check Valve/Bleed Orifice
Failure.7. Check for function/secure orifice insert in
O/D piston retainer.
DELAYED 3-4 UPSHIFT
(SLOW TO ENGAGE)1. Fluid Level Low. 1. Add fluid and check for leaks.
2. Throttle Valve Cable Mis-adjusted. 2. Adjust throttle valve cable.
3. Overdrive Clutch Pack Worn/
Burnt.3. Remove unit and rebuild clutch pack.
4. TPS Faulty. 4. Test with DRBTscan tool and replace as
necessary
5. Overdrive Clutch Bleed Orifice
Plugged.5. Disassemble transmission and replace
orifice.
6. Overdrive Solenoid or Wiring
Shorted/Open.6. Test solenoid and check wiring for
loose/corroded connections or shorts/
grounds. Replace solenoid if faulty and
repair wiring if necessary.
7. Overdrive Excess Clearance. 7. Remove unit. Measure end play and
select proper spacer.
8. O/D Check Valve Missing or
Stuck.8. Check for presence of check valve.
Repair or replace as required.
TORQUE CONVERTER
LOCKS UP IN SECOND
AND/OR THIRD GEARLockup Solenoid, Relay or Wiring
Shorted/Open.Test solenoid, relay and wiring for
continuity, shorts or grounds. Replace
solenoid and relay if faulty. Repair wiring
and connectors as necessary.
HARSH 1-2, 2-3, 3-4 OR
3-2 SHIFTSLockup Solenoid Malfunction. Remove valve body and replace solenoid
assembly.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 155
AUTOMATIC TRANSMISSION - 48RE (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS. 1. Fluid Lines and Fittings Loose/
Leaks/Damaged.1. Tighten fittings. If leaks persist, replace
fittings and lines if necessary.
2. Fill Tube (where tube enters case)
Leaks/Damaged.2. Replace tube seal. Inspect tube for
cracks in fill tube.
3. Pressure Port Plug Loose
Loose/Damaged.3. Tighten to correct torque. Replace plug
or reseal if leak persists.
4. Pan Gasket Leaks. 4. Tighten pan screws (150 in. lbs.). If leaks
persist, replace gasket.
5. Valve Body Manual Lever Shaft
Seal Leaks/Worn.5. Replace shaft seal.
6. Rear Bearing Access Plate Leaks. 6. Replace gasket. Tighten screws.
7. Gasket Damaged or Bolts are
Loose.7. Replace bolts or gasket or tighten both.
8. Adapter/Extension Gasket
Damaged Leaks/Damaged.8. Replace gasket.
9. Park/Neutral Switch, or
Transmission Range Sensor
Leaks/Damaged.9. Replace switch and gasket.
10. Converter Housing Area Leaks. 10. Check for leaks at seal caused by worn
seal or burr on converter hub (cutting seal),
worn bushing, missing oil return, oil in front
pump housing or hole plugged. Check for
leaks past O-ring seal on pump or past
pump-to-case bolts; pump housing porous,
oil coming out vent due to overfill or leak
past front band shaft access plug.
11. Pump Seal Leaks/Worn/
Damaged.11. Replace seal.
12. Torque Converter Weld
Leak/Cracked Hub.12. Replace converter.
13. Case Porosity Leaks. 13. Replace case.
NOISY OPERATION IN
FOURTH GEAR ONLY1. Overdrive Clutch Discs, Plates or
Snap Rings Damaged.1. Remove unit and rebuild clutch pack.
2. Overdrive Piston or Planetary
Thrust Bearing Damaged.2. Remove and disassemble unit. Replace
either thrust bearing if damaged.
3. Output Shaft Bearings Scored/
Damaged.3. Remove and disassemble unit. Replace
either bearing if damaged.
4. Planetary Gears Worn/Chipped. 4. Remove and overhaul overdrive unit.
5. Overdrive Unit Overrunning Clutch
Rollers Worn/Scored.5. Remove and overhaul overdrive unit.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 157
AUTOMATIC TRANSMISSION - 48RE (Continued)

STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR
Damaged or worn threads in the aluminum trans-
mission case and valve body can be repaired by the
use of Heli-CoilsŸ, or equivalent. This repair con-
sists of drilling out the worn-out damaged threads.
Then tap the hole with a special Heli-CoilŸ tap, or
equivalent, and installing a Heli-CoilŸ insert, or
equivalent, into the hole. This brings the hole back to
its original thread size.
Heli-CoilŸ, or equivalent, tools and inserts are
readily available from most automotive parts suppli-
ers.
REMOVAL
NOTE: The overdrive unit can be removed and ser-
viced separately. It is not necessary to remove the
entire transmission assembly to perform overdrive
unit repairs.
(1) Disconnect battery negative cable.
(2) Raise vehicle.
(3) Remove the transfer case skid plate (Fig. 12), if
equipped.(4) Disconnect and lower or remove necessary
exhaust components.
(5) Remove engine-to-transmission struts.
(6) Remove starter motor. (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL)
(7) Disconnect and remove the crankshaft position
sensor. (Refer to 14 - FUEL SYSTEM/FUEL INJEC-
TION/CRANKSHAFT POSITION SENSOR -
REMOVAL) Retain the sensor attaching bolts.
(8) If transmission is being removed for overhaul,
remove transmission oil pan, drain fluid and reinstall
pan.
(9) Remove torque converter access cover.
(10) Rotate crankshaft in clockwise direction until
converter bolts are accessible. Then remove bolts one
at a time. Rotate crankshaft with socket wrench on
dampener bolt.
(11) Mark propeller shaft and axle yokes for
assembly alignment. Then disconnect and remove
propeller shaft. On4x4models, remove both propel-
ler shafts. (Refer to 3 - DIFFERENTIAL & DRIV-
ELINE/PROPELLER SHAFT/PROPELLER SHAFT -
REMOVAL)
(12) Disconnect wires from the transmission range
sensor and transmission solenoid connector.
(13) Disconnect gearshift cable (Fig. 13) from the
transmission.
Fig. 12 Transfer Case Skid Plate
1 - FRAME RAIL
2 - SKID PLATE
3 - BOLTS (6)
Fig. 13 Gearshift Cable At Transmission
1 - GEARSHIFT CABLE
2 - TRANSMISSION MANUAL LEVER
3 - CABLE SUPPORT BRACKET
21 - 158 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)