2003 DODGE RAM 48RE fill

Miles 3,000 6,000 9,000 12,000 15,000
(Kilometers) (5 000) (10 000) (14 000) (19 000) (24 000)
Change engine oil and engine oil filter.XXXX X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings.X
Inspect engine air cleaner filter, replace
if necessary.X
Miles 18,000 21,000 24,000 27,000 30,000
(Kilometers) (29 000) (34 000) (38 000) (43 000) (48 000)
Change engine oil and engine oil filter.XXXX X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX X
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings. X
Inspect engine air cleaner filter, replace
if necessary.X
Replace spark plugs.X
Inspect PCV valve, replace as necessary.X*
Drain and refill automatic tranmission fluid,
change filter and adjust bands (46RE/47RE/
48RE).³X
Drain and refill automatic tranmission fluid
and change main sump filter (45RFE/
545RFE only).³X
Miles 33,000 36,000 39, 000 42,000 45,000
(Kilometers) (53 000) (58 000) (62 000) (67 000) (72 000)
Change engine oil and engine oil filter.XXXX X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings. X
Inspect engine air cleaner filter, replace
if necessary.X
DRLUBRICATION & MAINTENANCE 0 - 7
MAINTENANCE SCHEDULES (Continued)

Miles 48,000 51,000 54,000 57,000 60,000
(Kilometers) (77 000) (82 000) (86 000) (91 000) (96 000)
Change engine oil and engine oil filter.XXXX X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XXX
Drain and refill transfer case fluid.X
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings. X X
Inspect engine air cleaner filter, replace
if necessary.X
Replace spark plugs.X
Replace ignition cables (5.7L/5.9L/8.0L).X
Inspect PCV valve, replace as necessary.X*
Drain and refill automatic tranmission fluid,
change filter and adjust bands (46RE/47RE/
48RE).X
Drain and refill automatic tranmission fluid
and change main sump filter (45RFE/
545RFE only).X
Miles 63,000 66,000 69,000 72,000 75,000
(Kilometers) (101 000) (106 000) (110 000) (115 000) (120 000)
Change engine oil and engine oil filter.XXXX
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX
Inspect engine air cleaner filter.X
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings.X
Inspect auto tension drive belt and replace
if required (3.7L/4.7L/5.7L/5.9L/8.0L).X
0 - 8 LUBRICATION & MAINTENANCEDR
MAINTENANCE SCHEDULES (Continued)

Miles 78,000 81,000 84,000 87,000 90,000
(Kilometers) (125 000) (130 000) (134 000) (139 000) (144 000)
Change engine oil and engine oil filter.XXXX X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XXX
Change rear axle fluid.X
Change front axle fluid (4X4).X
Inspect brake linings. X
Inspect engine air cleaner filter, replace
if necessary.X
Replace spark plugs.X
Inspect PCV valve, replace as necessary.X*
Inspect auto tension drive belt and replace
if required (3.7L/4.7L/5.7L/5.9L/8.0L).X³
Drain and refill automatic tranmission fluid,
change filter and adjust bands (46RE/47RE/
48RE).X
Drain and refill automatic tranmission fluid
and change main sump and spin-on cooler
return filter (if equipped) [45RFE/545RFE
only].X
Miles 93,000 96,000 99,000 100,000 102,000
(Kilometers) (149 000) (154 000) (158 000) (160 000) (163 000)
Change engine oil and engine oil filter. X X X X
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX
Flush and replace engine coolant. X
Flush and replace Power Steering Fluid. X
Inspect brake linings. X
DRLUBRICATION & MAINTENANCE 0 - 9
MAINTENANCE SCHEDULES (Continued)

Miles 105,000 108,000 111,000 114,000 117,000 120,000
(Kilometers) (168 000) (173 000) (178 000) (182 000) (187 000) (192 000)
Change engine oil and engine
oil filter.XXXXX X
Lubricate outer tie rod ends
2500/3500 (4X4) models only.XXX
Drain and refill transfer case
fluid.X
Change rear axle fluid. X X
Change front axle fluid (4X4). X X
Inspect brake linings. X X
Inspect engine air cleaner
filter, replace if necessary.XX
Replace spark plugs.X
Replace ignition cables
(5.7L/5.9L/8.0L).X
Inspect PCV valve, replace
as necessary.X*
Inspect auto tension drive belt
and replace if required
(3.7L/4.7L/5.7L/5.9L/8.0L).X³ X³
Drain and refill automatic
tranmission fluid, change filter
and adjust bands (46RE/
47RE/48RE).X
Drain and refill automatic
tranmission fluid and change
main sump filter (45RFE/
545RFE only).X
* This maintenance is recommended by the manu-
facture to the owner but is not required to maintain
the emissions warranty.
³ This maintenance is not required if previously
replaced.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
Retain all receipts.
0 - 10 LUBRICATION & MAINTENANCEDR
MAINTENANCE SCHEDULES (Continued)

Miles 72,000 78,000 84,000 90,000 96,000 100,000
(Kilometers) (115 000) (125 000) (134 000) (144 000) (154 000) (160 000)
[Months] [72] [78] [84] [90] [96]
Change engine oil and engine oil filter.XXXXX
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XXXXX
Drain and refill transfer case fluid. X
Flush and replace engine coolant, if not
done at 60 mos.X
Flush and replace Power Steering Fluid.X
Inspect brake linings. X X
Replace engine air cleaner filter.X
Replace spark plugs.X
Replace ignition cables (5.7L/5.9L/
8.0L).X
Inspect PCV valve, replace as
necessary.X*
Inspect auto tension drive belt and
replace if required (3.7L/4.7L/5.7L/5.9L/
8.0L).X
Drain and refill automatic tranmission
fluid, change filter and adjust bands
(46RE/47RE/48RE).X
Drain and refill automatic tranmission
fluid and change main sump filter and
spin-on cooler return filter (if equipped)
[45RFE/545RFE only].X
Miles 102,000 108,000 114,000 120,000
(Kilometers) (163 000) (173 000) (182 000) (192 000)
[Months] [102] [108] [114] [120]
Change engine oil and engine oil filter. X X X X
Check transfer case fluid level.X
Lubricate outer tie rod ends 2500/3500 (4X4) models only. X X X X
Inspect brake linings. X
Inspect auto tension drive belt and replace if required
(3.7L/4.7L/5.7L/5.9L/8.0L).X³X³
Replace engine air cleaner filter.X
Replace spark plugs.X
* This maintenance is recommended by the manu-
facture to the owner but is not required to maintain
the emissions warranty.
³ This maintenance is not required if previously
replaced.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
Retain all receipts.WARNING: You can be badly injured working on or
around a motor vehicle. Do only that service work
for which you have the knowledge and the right
equipment. If you have any doubt about your ability
to perform a service job, take your vehicle to a
competent mechanic.
0 - 12 LUBRICATION & MAINTENANCEDR
MAINTENANCE SCHEDULES (Continued)

AUTOMATIC TRANSMISSION - 48RE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 48RE
DESCRIPTION........................312
OPERATION..........................314
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION.....................320
DIAGNOSIS AND TESTING - PRELIMINARY. . 320
DIAGNOSIS AND TESTING - ROAD
TESTING...........................320
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST....................321
DIAGNOSIS AND TESTING - AIR TESTING
TRANSMISSION CLUTCH AND BAND
OPERATION........................324
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK................324
DIAGNOSIS AND TESTING - DIAGNOSIS
CHARTS...........................325
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR.....................337
REMOVAL............................337
DISASSEMBLY........................339
CLEANING...........................345
INSPECTION.........................345
ASSEMBLY...........................346
INSTALLATION........................353
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS.............355
SPECIFICATIONS
TRANSMISSION.....................368
SPECIAL TOOLS
RE TRANSMISSION..................370
ACCUMULATOR
DESCRIPTION........................372
OPERATION..........................373
INSPECTION.........................373
BANDS
DESCRIPTION........................373
OPERATION..........................374
ADJUSTMENTS
ADJUSTMENT - BANDS...............374
BRAKE TRANSMISSION SHIFT INTERLOCK
SYSTEM
DESCRIPTION........................375
OPERATION..........................375
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK......375
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK...................376ELECTRONIC GOVERNOR
DESCRIPTION........................376
OPERATION..........................377
REMOVAL............................378
INSTALLATION........................379
EXTENSION HOUSING SEAL
REMOVAL............................380
INSTALLATION........................380
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL.............381
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID.......................381
DIAGNOSIS AND TESTING - FLUID
CONTAMINATION....................381
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK............................381
STANDARD PROCEDURE - FLUID AND
FILTER REPLACEMENT...............383
STANDARD PROCEDURE - TRANSMISSION
FILL...............................383
FRONT CLUTCH
DESCRIPTION........................384
OPERATION..........................384
DISASSEMBLY........................384
INSPECTION.........................385
ASSEMBLY...........................386
FRONT SERVO
DESCRIPTION........................387
OPERATION..........................387
DISASSEMBLY........................388
CLEANING...........................388
INSPECTION.........................388
ASSEMBLY...........................388
GEARSHIFT CABLE
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE.............................389
REMOVAL............................389
INSTALLATION........................390
ADJUSTMENTS
GEARSHIFT CABLE..................391
OIL PUMP
DESCRIPTION........................392
OPERATION..........................392
DISASSEMBLY........................393
CLEANING...........................393
INSPECTION.........................393
ASSEMBLY...........................393
21 - 310 AUTOMATIC TRANSMISSION - 48REDR

FOURTH GEAR POWERFLOW
Fourth gear overdrive range is electronically con-
trolled and hydraulically activated. Various sensor
inputs are supplied to the powertrain control module
to operate the overdrive solenoid on the valve body.
The solenoid contains a check ball that opens and
closes a vent port in the 3-4 shift valve feed passage.
The overdrive solenoid (and check ball) are not ener-
gized in first, second, third, or reverse gear. The vent
port remains open, diverting line pressure from the
2-3 shift valve away from the 3-4 shift valve. The
overdrive control switch must be in the ON position
to transmit overdrive status to the PCM. A 3-4
upshift occurs only when the overdrive solenoid is
energized by the PCM. The PCM energizes the over-
drive solenoid during the 3-4 upshift. This causes the
solenoid check ball to close the vent port allowing
line pressure from the 2-3 shift valve to act directly
on the 3-4 upshift valve. Line pressure on the 3-4
shift valve overcomes valve spring pressure moving
the valve to the upshift position. This action exposes
the feed passages to the 3-4 timing valve, 3-4 quick
fill valve, 3-4 accumulator, and ultimately to the
overdrive piston. Line pressure through the timing
valve moves the overdrive piston into contact with
the overdrive clutch. The direct clutch is disengaged
before the overdrive clutch is engaged. The boost
valve provides increased fluid apply pressure to the
overdrive clutch during 3-4 upshifts, and when accel-
erating in fourth gear. The 3-4 accumulator cushions
overdrive clutch engagement to smooth 3-4 upshifts.
The accumulator is charged at the same time as
apply pressure acts against the overdrive piston.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION
Automatic transmission problems can be a result of
poor engine performance, incorrect fluid level, incor-
rect linkage or cable adjustment, band or hydraulic
control pressure adjustments, hydraulic system mal-
functions or electrical/mechanical component mal-
functions. Begin diagnosis by checking the easily
accessible items such as: fluid level and condition,
linkage adjustments and electrical connections. A
road test will determine if further diagnosis is neces-
sary.
DIAGNOSIS AND TESTING - PRELIMINARY
Two basic procedures are required. One procedure
for vehicles that are drivable and an alternate proce-
dure for disabled vehicles (will not back up or move
forward).
VEHICLE IS DRIVEABLE
(1) Check for transmission fault codes using DRBt
scan tool.
(2) Check fluid level and condition.
(3) Adjust throttle and gearshift linkage if com-
plaint was based on delayed, erratic, or harsh shifts.
(4) Road test and note how transmission upshifts,
downshifts, and engages.
(5) Perform hydraulic pressure test if shift prob-
lems were noted during road test.
(6) Perform air-pressure test to check clutch-band
operation.
VEHICLE IS DISABLED
(1) Check fluid level and condition.
(2) Check for broken or disconnected gearshift or
throttle linkage.
(3) Check for cracked, leaking cooler lines, or loose
or missing pressure-port plugs.
(4) Raise and support vehicle on safety stands,
start engine, shift transmission into gear, and note
following:
(a) If propeller shaft turns but wheels do not,
problem is with differential or axle shafts.
(b) If propeller shaft does not turn and transmis-
sion is noisy, stop engine. Remove oil pan, and
check for debris. If pan is clear, remove transmis-
sion and check for damaged drive plate, converter,
oil pump, or input shaft.
(c) If propeller shaft does not turn and transmis-
sion is not noisy, perform hydraulic-pressure test to
determine if problem is hydraulic or mechanical.
DIAGNOSIS AND TESTING - ROAD TESTING
Before road testing, be sure the fluid level and con-
trol cable adjustments have been checked and
adjusted if necessary. Verify that diagnostic trouble
codes have been resolved.
Observe engine performance during the road test.
A poorly tuned engine will not allow accurate analy-
sis of transmission operation.
Operate the transmission in all gear ranges. Check
for shift variations and engine flare which indicates
slippage. Note if shifts are harsh, spongy, delayed,
early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means
clutch, band or overrunning clutch problems. If the
condition is advanced, an overhaul will be necessary
to restore normal operation.
A slipping clutch or band can often be determined
by comparing which internal units are applied in the
various gear ranges. The Clutch and Band Applica-
tion chart provides a basis for analyzing road test
results.
21 - 320 AUTOMATIC TRANSMISSION - 48REDR
AUTOMATIC TRANSMISSION - 48RE (Continued)

CLUTCH AND BAND APPLICATION CHART
SHIFT
LEVER
POSITIONTRANSMISSION CLUTCHES AND BANDS OVERDRIVE CLUTCHES
FRONT
CLUTCHFRONT
BANDREAR
CLUTCHREAR
BANDOVER-
RUNNING
CLUTCHOVER-
DRIVE
CLUTCHDIRECT
CLUTCHOVER-
RUNNING
CLUTCH
Reverse X X X
Drive -
FirstXXXX
Drive -
SecondXX X X
Drive -
ThirdXX XX
Drive -
FourthXX X
Manual
SecondXX X X
Manual
FirstXXX X X
Note that the rear clutch is applied in all forward
ranges (D, 2, 1). The transmission overrunning clutch
is applied in first gear (D, 2 and 1 ranges) only. The
rear band is applied in 1 and R range only.
Note that the overdrive clutch is applied only in
fourth gear and the overdrive direct clutch and over-
running clutch are applied in all ranges except fourth
gear.
For example: If slippage occurs in first gear in D
and 2 range but not in 1 range, the transmission
overrunning clutch is faulty. Similarly, if slippage
occurs in any two forward gears, the rear clutch is
slipping.
Applying the same method of analysis, note that
the front and rear clutches are applied simulta-
neously only in D range third and fourth gear. If the
transmission slips in third gear, either the front
clutch or the rear clutch is slipping.
If the transmission slips in fourth gear but not in
third gear, the overdrive clutch is slipping. By select-
ing another gear which does not use these clutches,
the slipping unit can be determined. For example, 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.
If slippage occurs during the 3-4 shift or only in
fourth gear, the overdrive clutch is slipping. Simi-
larly, if the direct clutch were to fail, the transmis-
sion would lose both reverse gear and overrun
braking in 2 position (manual second gear).
If the transmission will not shift to fourth gear, the
control switch, overdrive solenoid or related wiring
may also be the problem cause.This process of elimination can be used to identify
a slipping unit and check operation. Proper use of
the Clutch and Band Application Chart is the key.
Although road test analysis will help determine the
slipping unit, the actual cause of a malfunction usu-
ally cannot be determined until hydraulic and air
pressure tests are performed. Practically any condi-
tion can be caused by leaking hydraulic circuits or
sticking valves.
Unless a malfunction is obvious, such as no drive
in D range first gear, do not disassemble the trans-
mission. Perform the hydraulic and air pressure tests
to help determine the probable cause.
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST
Hydraulic test pressures range from a low of one
psi (6.895 kPa) governor pressure, to 300 psi (2068
kPa) at the rear servo pressure port in reverse.
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3292 has a 100 psi range
and is used at the accumulator, governor, and front
servo ports. Test Gauge C-3293-SP has a 300 psi
range and is used at the rear servo and overdrive
ports where pressures exceed 100 psi.
Pressure Test Port Locations
Test ports are located at both sides of the transmis-
sion case (Fig. 9).
Line pressure is checked at the accumulator port
on the right side of the case. The front servo pressure
port is at the right side of the case just behind the
filler tube opening.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 321
AUTOMATIC TRANSMISSION - 48RE (Continued)