1998 DODGE RAM 1500 Removal

DIAGNOSIS AND TESTING
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the
result of a leak, inadequate lubricant fill or an incor-
rect lubricant level check. Leaks can occur at the
mating surfaces of the gear case, adaptor or exten-
sion housing, or from the front/rear seals. A sus-
pected leak could also be the result of an overfill
condition.
Leaks at the rear of the extension or adapter hous-
ing will be from the housing oil seals. Leaks at com-
ponent mating surfaces will probably be the result of
inadequate sealer, gaps in the sealer, incorrect bolt
tightening or use of a non-recommended sealer.
A leak at the front of the transmission will be from
either the front bearing retainer or retainer seal.
Lubricant may be seen dripping from the clutch
housing after extended operation. If the leak is
severe, it may also contaminate the clutch disc caus-
ing the disc to slip, grab and or chatter.
A correct lubricant level check can only be made
when the vehicle is level. Also allow the lubricant to
settle for a minute or so before checking. These rec-
ommendations will ensure an accurate check and
avoid an underfill or overfill condition. Always check
the lubricant level after any addition of fluid to avoid
an incorrect lubricant level condition.
HARD SHIFTING
Hard shifting is usually caused by a low lubricant
level, improper or contaminated lubricants. The con-
sequence of using non-recommended lubricants is
noise, excessive wear, internal bind and hard shift-
ing. Substantial lubricant leaks can result in gear,
shift rail, synchro, and bearing damage. If a leak
goes undetected for an extended period, the first indi-
cations of component damage are usually hard shift-
ing and noise.
Shift component damage or damaged clutch pres-
sure plate or disc are additional probable causes of
increased shift effort. Worn/damaged pressure plate
or disc can cause incorrect release. If clutch problem
is advanced, gear clash during shifts can result.
Worn or damaged synchro rings can cause gear clash
when shifting into any forward gear. In some new or
rebuilt transmissions, new synchro rings may tend to
stick slightly causing hard or noisy shifts. In most
cases this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise dur-
ing normal operation. Rotating gears generate a mild
whine that is audible, but generally only at extreme
speeds.
Severe highly audible transmission noise is gener-
ally the initial indicator of a lubricant problem.
Insufficient, improper or contaminated lubricant will
promote rapid wear of gears, synchros, shift rails,
forks and bearings. The overheating caused by a
lubricant problem, can also lead to gear and bearing
damage.
REMOVAL
(1) Disconnect battery negative cable.
(2) Shift transmission into Neutral.
(3) Remove shift boot bezel screws and slide boot
upward on shift lever extension.
(4) Remove shift lever extension from the shift
tower and lever assembly.
(5) Raise vehicle on hoist.
(6) Remove skid plate, if equipped.
(7) Drain lubricant if transmission will be disas-
sembled for service.
(8) Mark propeller shaft/shafts and companion
flange yoke/yokes for installation reference and
remove propeller shaft/shafts.
(9) Disconnect harness from clips on transmission
housing.
(10) Remove transfer case linkage if equipped.
(11) Remove transfer case mounting nuts and
remove transfer case if equipped.
(12) Remove slave cylinder mounting nut and
remove cylinder (Fig. 2).
Fig. 2 SLAVE CYLINDER
1 - MOUNTING NUTS
2 - SLAVE CYLINDER
DRMANUAL TRANSMISSION - NV3500 21 - 3
MANUAL TRANSMISSION - NV3500 (Continued)

(13) Remove starter motor, structural dust cover
bolts to clutch housing, dust shield bolt and suspen-
sion crossmember (Fig. 3).
CAUTION: Do not remove structural dust cover
from enigne block. If cover is removed clutch hous-
ing and cover must be aligned with the engine.
(14) Remove exhaust pipe from the exhaust mani-
folds.
(15) Support engine with adjustable jack stand
and wood block.
(16) Support and secure transmission to a trans-
mission jack with safety chains.
(17) Remove bolts from the rear transmission
mount.
(18) Remove the rear crossmember and transmis-
sion mount (Fig. 4).
(19) Remove bolts attaching transmission to the
engine.
(20) Move transmission rearward until input shaft
is clear of clutch disc and pressure plate. Then lower
jack and remove transmission from under vehicle.
DISASSEMBLY
FRONT HOUSING
(1) Shift transmission into Neutral.
(2) If lubricant was not drained out of transmis-
sion during removal, remove drain plug and drain
lubricant.
(3) Inspect drain plug magnet for debris.
(4) Remove backup light switch located on passen-
ger side of rear housing (Fig. 5).
(5) Remove shift tower bolts and remove tower and
lever assembly (Fig. 6).
Fig. 3 DUST COVER
1 - DUST SHIELD
2 - STARTER MOTOR
3 - DUST COVER
4 - CROSSMEMBER
Fig. 4 CROSSMEMBER
1 - TRANSMISSION MOUNT
2 - CROSSMEMBER
Fig. 5 BACKUP LIGHT SWITCH
1 - BACKUP LIGHT SWITCH
Fig. 6 SHIFT TOWER
1 - SHIFT TOWER
2 - SHIFT SOCKET
3 - SEAL
21 - 4 MANUAL TRANSMISSION - NV3500DR
MANUAL TRANSMISSION - NV3500 (Continued)

(19) Install second gear needle bearing on shaft
(Fig. 65).
(20) Install second gear onto shaft and bearing
(Fig. 66). Verify second gear is seated on synchro
components.
(21) Install two-piece thrust washer with halves
seated in the shaft groove and washer lugs seated in
shaft lug bores (Fig. 67). Verify i.d. grooves and
markings noted during removal are facing the correct
direction.
(22) Start retaining ring around two-piece thrust
washer (Fig. 68). Verify locating dimple is between
thrust washer halves.
Fig. 65 SECOND GEAR BEARING
1 - SECOND GEAR BEARING
2 - COLLAR
Fig. 66 SECOND GEAR
1 - COLLAR
2 - 1-2 SYNCHRO ASSEMBLY
3 - BEARING
4 - SECOND GEAR
Fig. 67 TWO-PIECE THRUST WASHER
1 - WASHER GROOVE IN SHAFT
2 - LUG BORE
3 - THRUST WASHER LUGS
4 - LUG BORE
5 - LUG
6 - WASHER HALF
Fig. 68 RETAINING RING
1 - THRUST WASHER RETAINING RING
2 - THRUST WASHER HALVES
3 - SECOND GEAR
4 - LOCATING DIMPLE
21 - 22 MANUAL TRANSMISSION - NV3500DR
MANUAL TRANSMISSION - NV3500 (Continued)

MANUAL TRANSMISSION - NV4500
TABLE OF CONTENTS
page page
MANUAL TRANSMISSION - NV4500
DESCRIPTION.........................43
OPERATION...........................43
DIAGNOSIS AND TESTING................44
REMOVAL.............................44
DISASSEMBLY.........................46
CLEANING............................62
INSPECTION..........................62
ASSEMBLY............................63
INSTALLATION.........................80
SPECIFICATIONS.......................81
SPECIAL TOOLS.......................81ADAPTER HOUSING SEAL
REMOVAL.............................85
INSTALLATION.........................85
EXTENSION HOUSING SEAL
REMOVAL.............................85
INSTALLATION.........................85
SHIFT MECHANISM
REMOVAL.............................86
INSTALLATION.........................87
SHIFT COVER
REMOVAL.............................87
INSTALLATION.........................87
MANUAL TRANSMISSION -
NV4500
DESCRIPTION
The NV4500 is a five speed constant mesh manual
transmission. All gear ranges including reverse are
synchronized. Fifth gear is an overdrive range. The
transmission has a cast iron gear case and aluminum
shift cover.
Two versions are used, a standard duty for 5.7L
applications and a heavy duty for V10 and Cummins
diesel applications. Main difference is a larger diam-
eter input shaft, for the heavy duty model.
Tapered roller bearings support the drive gear,
mainshaft and countershaft in the gear case. Roller
bearings in the drive gear support the forward end of
the mainshaft. The mainshaft gears are all supported
on caged type roller bearings. Drive gear thrust reac-
tion is controlled by a needle type thrust bearing.
The bearing is located at the forward end of the
mainshaft.
The transmission is a top loader style. The shift
lever is located in a shifter tower which is bolted to
the shift cover and operates the shift forks and rails
directly. The shift forks and rails are all located
within the aluminum cover which is bolted to the top
of the gear case.
IDENTIFICATION
The transmission identification tag is attached to
the driver side PTO cover (Fig. 1).
The tag provides the transmission model number,
build date and part number. Be sure to reinstall the
I.D. tag if removed during service. The information
on the tag is essential to correct parts ordering.
OPERATION
The manual transmission receives power through
the clutch assembly from the engine. The clutch disc
is splined to the transmission input shaft and is
turned at engine speed at all times that the clutch is
engaged. The input shaft is connected to the trans-
mission countershaft through the mesh of fourth
speed gear on the input shaft and the fourth counter-
shaft gear. At this point all the transmission gears
are spinning.
Fig. 1 IDENTIFICATION TAG LOCATION
1 - PTO COVER
2 - I.D. TAG
DRMANUAL TRANSMISSION - NV4500 21 - 43

The driver selects a particular gear by moving the
shift lever to the desired gear position. This move-
ment moves the internal transmission shift compo-
nents to begin the shift sequence. As the shift lever
moves the selected shift rail, the shift fork attached
to that rail begins to move. The fork is positioned in
a groove in the outer circumference of the synchro-
nizer sleeve. As the shift fork moves the synchronizer
sleeve, the synchronizer begins to speed-up or slow
down the selected gear (depending on whether the
driver is up-shifting or down-shifting). The synchro-
nizer does this by having the synchronizer hub
splined to the mainshaft, or the countershaft in some
cases, and moving the blocker ring into contact with
the gear's friction cone. As the blocker ring and fric-
tion cone come together, the gear speed is brought up
or down to the speed of the synchronizer. As the two
speeds match, the splines on the inside of the syn-
chronizer sleeve become aligned with the teeth on
the blocker ring and the friction cone and eventually
will slide over the teeth, locking the gear to the
mainshaft, or countershaft, through the synchronizer.
DIAGNOSIS AND TESTING
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the
result of a leak, inadequate lubricant fill or an incor-
rect lubricant level check. A correct lubricant level
check can only be made when the vehicle is level.
Also allow the lubricant to settle for a minute or so
before checking. These recommendations will ensure
an accurate check and avoid an underfill or overfill
condition. Always check the lubricant level after any
addition of fluid to avoid an incorrect lubricant level
condition.
Leaks can occur at the mating surfaces of the gear
case, adaptor or extension housing, or from the front/
rear seals. A suspected leak could also be the result
of an overfill condition. Leaks at the rear of the
extension or adapter housing will be from the hous-
ing oil seals. Leaks at component mating surfaces
will probably be the result of inadequate sealer, gaps
in the sealer, incorrect bolt tightening or use of a
non-recommended sealer. A leak at the front of the
transmission will be from either the front bearing
retainer or retainer seal. Lubricant may be seen drip-
ping from the clutch housing after extended opera-
tion. If the leak is severe, it may also contaminate
the clutch disc causing the disc to slip, grab and or
chatter.
HARD SHIFTING
Hard shifting is usually caused by a low lubricant
level, improper or contaminated lubricants. The con-
sequence of using non-recommended lubricants isnoise, excessive wear, internal bind and hard shift-
ing. Substantial lubricant leaks can result in gear,
shift rail, synchro, and bearing damage. If a leak
goes undetected for an extended period, the first indi-
cations of component damage are usually hard shift-
ing and noise.
Component damage, incorrect clutch adjustment or
damaged clutch pressure plate or disc are additional
probable causes of increased shift effort. Incorrect
adjustment or a worn/damaged pressure plate or disc
can cause incorrect release. If clutch problem is
advanced, gear clash during shifts can result. Worn
or damaged synchro rings can cause gear clash when
shifting into any forward gear. In some new or
rebuilt transmissions, new synchro rings may tend to
stick slightly causing hard or noisy shifts. In most
cases this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise dur-
ing normal operation. Rotating gears generate a mild
whine that is audible, but generally only at extreme
speeds. Severe highly audible transmission noise is
generally the initial indicator of a lubricant problem.
Insufficient, improper or contaminated lubricant
will promote rapid wear of gears, synchros, shift
rails, forks and bearings. The overheating caused by
a lubricant problem, can also lead to gear breakage.
REMOVAL
(1) Shift transmission into Neutral.
(2) Remove shift boot screws from floorpan and
slide boot upward on the shift lever.
(3) Remove shift lever extension from shift tower
and lever assembly.
(4) Remove shift tower bolts (Fig. 2).
Fig. 2 SHIFT TOWER
1 - SHIFT TOWER
2 - SHIFTER
3 - BOLTS
21 - 44 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)

MAINSHAFT
NOTE: Gear and synchro components can be
installed backwards. Paint or scribe gear and syn-
chro components for installation reference. Then
stack geartrain parts in order of removal.
(1) Remove drive gear thrust bearing from end of
mainshaft, if not previously removed.
(2) Place 3-4 gear in a press with support under
3rd gear and Remove 3-4 synchro hub, third gear
stop ring and third gear as an assembly (Fig. 43).
(3) Remove third gear bearing from mainshaft
(Fig. 44).
(4) Remove third gear bearing spacer (Fig. 45).
(5) Remove second gear thrust washer snap ring
from mainshaft (Fig. 45).
Fig. 43 THIRD GEAR, STOP RING, AND 3-4 HUB
1 - THIRD GEAR
2 - THIRD GEAR STOP RING
3 - 3-4 SYNCHRO HUB
Fig. 44 THIRD GEAR BEARING
1 - THIRD GEAR NEEDLE BEARING
Fig. 45 SNAP RING AND THIRD GEAR BEARING
SPACER
1 - SECOND GEAR THRUST WASHER
2 - THRUST WASHER SNAP RING
3 - THIRD GEAR BEARING SPACER
21 - 56 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)

(22) Remove bearing puller tools and rear main-
shaft bearing from output shaft.
(23) Remove reverse gear thrust washer (Fig. 59).
(24) Remove reverse gear and synchro components
as assembly (Fig. 60).CAUTION: Do not disassemble synchro compo-
nents unless they are damaged. If synchro sleeve
or struts require service, mark position of sleeve on
hub before removal. Correct sleeve position is
important as sleeve can be installed backwards
causing shift problems.
(25) Remove reverse gear bearing assembly from
mainshaft (Fig. 60).
(26) Remove reverse gear bearing spacer from
mainshaft (Fig. 61).
(27) Remove reverse clutch gear snap ring (Fig.
61). Heavy duty snap ring pliers will be required to
spread the ring far enough to remove it.
Fig. 58 MAINSHAFT REAR BEARING
1-JAWS
2 - COLLAR
3 - FLANGE
4 - MAINSHAFT
5 - PULLER
6 - TIGHTENING WRENCH
7 - HOLDING WRENCH
8 - RODS
Fig. 59 REVERSE GEAR THRUST WASHER
1 - REVERSE GEAR
2 - THRUST WASHER
Fig. 60 REVERSE GEAR, BEARING, AND STOP
RING
1 - FIRST GEAR
2 - REVERSE GEAR ASSEMBLY
3 - BEARING ASSEMBLY
4 - STOP RING
Fig. 61 REVERSE GEAR BEARING SPACER AND
FIRST GEAR SNAP RING
1 - CLUTCH GEAR SNAP RING
2 - REVERSE GEAR BEARING SPACER
DRMANUAL TRANSMISSION - NV4500 21 - 61
MANUAL TRANSMISSION - NV4500 (Continued)

ADAPTER HOUSING SEAL
REMOVAL
(1) Raise and support vehicle.
(2) Mark the propeller shafts and yokes for instal-
lation reference and remove the shafts.
(3) Support transmission with a transmission jack.
(4) Remove engine rear support.
(5) Remove transfer case.
(6) Remove adapter housing seal with a pry tool or
slide hammer mounted screw (Fig. 130).
INSTALLATION
(1) Install adapter housing seal with Installer
C-3860-A and Handle C-4171.
(2) Install transfer case.
(3) Install propeller shafts with reference marks
aligned.
(4) Fill transfer case and transmission to proper
level.
(5) Remove support and lower vehicle.
EXTENSION HOUSING SEAL
REMOVAL
(1) Mark the propeller shaft and yoke for installa-
tion reference.
(2) Remove the propeller shaft.
(3) Remove extension housing seal (Fig. 131) using
Remover C-3985-B.
(4) On heavy duty 4X2 vehicles, remove extension
housing seal with a pry tool or a slide hammer
mounted screw.(5) On light duty transmissions, remove the exten-
sion housing bushing with Remover 6957.
(6) On heavy duty transmissions, remove the
extension housing bushing with Remover 8155.
INSTALLATION
(1) Install housing bushing with Handle C-4171
(Fig. 132) and Installer.
²Light Duty - Installer 6951
²Heavy Duty - Installer 8161
Fig. 130 Adapter Housing (4±Wheel Drive Models)
1 - ADAPTER HOUSING
2 - SEAL
Fig. 131 EXTENSION HOUSING AND SEAL (4X2)
1 - EXTENSION HOUSING
2 - SEAL
Fig. 132 Extension Housing Bushing
1 - HANDLE
2 - INSTALLER
3 - EXTENSION HOUSING
DRMANUAL TRANSMISSION - NV4500 21 - 85