1998 DODGE RAM 1500 ECU

INSTALLATION
NOTE: If a new transmission is being installed, use
all components supplied with the new transmission.
For example, if a new shift tower is supplied, do not
re-use the original shift tower.
(1) Clean transmission front housing mounting
surface.
(2) Apply light coat of Mopar high temperature
bearing grease or equivalent to contact surfaces (Fig.
126) of following components:
²release fork ball stud.
²release bearing slide surface.
²input shaft splines.
²release bearing bore.
²propeller shaft slip yoke.
(3) Support and secure transmission to jack.
(4) Raise and align transmission input shaft with
clutch disc, then slide transmission into place.
(5) Verify front housing is fully seated. Install
transmission bolts without washers and tighten bolts
into the engine to 41 N´m (30 ft. lbs.). Tighten the
bolts with washers into the transmission to 68 N´m
(50 ft. lbs.) (Fig. 127).(6) Install rear crossmember and tighten nuts to
102 N´m (75 ft. lbs.).
(7) Install transmission rear mounting bolts and
tighten to 68 N´m (50 ft. lbs.).
(8) Install front dust shield tighten bolt to 4.5 N´m
(40 in. lbs.). If cover was removed, install onto the
transmission and engine(Refer to 9 - ENGINE/EN-
GINE BLOCK/STRUCTURAL COVER - INSTALLA-
TION).
(9) Install structural dust cover and tighten the
bolts to 54 N´m (40 ft. lbs.).
(10) Install starter motor.
(11) Install suspension crossmember and tighten
nuts to 102 N´m (75 ft. lbs.).
(12) Connect transmission harnesses to clips on
case and connect switches.
(13) Install slave cylinder and tighten cylinder
nuts to 23 N´m (200 in. lbs.).
(14) Install transfer case and transfer case linkage
if equipped.
(15) Remove transmission jack.
(16) Install propeller shaft/shafts with reference
marks aligned.
(17) Install exhaust on the exhaust manifolds.
(18) Fill transmission with lubricant. Correct fill
level is to bottom edge of fill plug hole.
Fig. 126 LUBRICATION POINTS
1 - RELEASE FORK
2 - FORK BALL STUD
3 - BEARING SLIDE SURFACE
4 - SPLINE
5 - RELEASE BEAING
Fig. 127 TRANSMISSION
1 - BOLT WITHOUT WASHER
2 - BOLT WITH WASHER
DRMANUAL TRANSMISSION - NV3500 21 - 39
MANUAL TRANSMISSION - NV3500 (Continued)

(5) Remove shift tower and isolator plate from
transmission shift cover.
(6) Raise and support vehicle.
(7) Remove skid plate, if equipped.
(8) Mark propeller shaft and axle yokes for instal-
lation reference and remove shaft/shafts.
(9) Remove exhaust system Y-pipe.
(10) Disconnect speed sensor and backup light
switch connectors.
(11) Support engine with safety stand and a wood
block.
(12) If transmission is to be disassembled, remove
drain bolt at bottom of PTO cover and drain lubri-
cant (Fig. 3).
TWO WHEEL DRIVE
(1) Remove bolts attaching transmission to rear
crossmember mount.
(2) Support and secure transmission with safety
chains to a transmission jack.
(3) Remove rear crossmember bolts and pry out
crossmenber.
(4) Remove clutch slave cylinder bolts and move
cylinder aside for clearance.
NOTE: The hydraulic linkage has a quick connect at
the slave cylinder. This fitting should not be discon-
nected.
(5) Remove transmission harness wires from clips
on transmission shift cover.
(6) Remove transmission to clutch housing bolts.
(7) Slide transmission and jack rearward until
input shaft clears clutch housing.
(8) Lower transmission jack and remove transmis-
sion from under vehicle.
FOUR WHEEL DRIVE
(1) Disconnect transfer case shift linkage at trans-
fer case range lever. Then remove transfer case shift
mechanism from transmission (Fig. 4).
(2) Support and secure transfer case to transmis-
sion jack with safety chains.
(3) Remove transfer case mounting nuts.
(4) Move transfer case rearward until input gear
clears transmission mainshaft.
(5) Lower transfer case assembly and move it from
under vehicle.
(6) Support and secure transmission with safety
chains to a transmission jack.
(7) Remove transmission harness from retaining
clips on transmission shift cover.
(8) Remove bolts/nuts attaching transmission
mount to rear crossmember.
(9) Remove rear crossmember bolts and pry out
crossmenber.
(10) Remove clutch slave cylinder splash shield, if
equipped.
(11) Remove clutch slave cylinder bolts and move
cylinder aside for clearance.
NOTE: The hydraulic linkage has a quick connect at
the slave cylinder. This fitting should not be discon-
nected.
(12) Remove transmission to clutch housing bolts.
(13) Slide transmission and jack rearward until
input shaft clears clutch housing.
(14) Lower transmission jack and remove trans-
mission from under vehicle.
Fig. 3 FILL AND DRAIN PLUGS
1 - PTO COVER
2 - DRAIN BOLT
3 - FILL PLUG
Fig. 4 TRANSFER CASE SHIFTER-TYPICAL
1 - TRANSMISSION
2 - TRANSFER CASE SHIFT MECHANISM
DRMANUAL TRANSMISSION - NV4500 21 - 45
MANUAL TRANSMISSION - NV4500 (Continued)

(12) Position second puller jaw on gear and in
notch of puller flange (Fig. 17). Slide Collar 6444-8
over puller jaws to hold them in place.
(13) Install Puller and Bolt 6444 on puller rods
and secure puller to rods with retaining nuts (Fig.
18). Tighten puller bolt to remove gear from shaft
splines.(14) Remove mainshaft rear bearing plate bolts
and remove fifth gear plate end play shims and bear-
ing cup (Fig. 19).
FRONT RETAINER
(1) Remove and discard front bearing retainer
bolts (Fig. 20).
CAUTION: Do not reuse retainer bolts.
(2) Lightly tap retainer back and forth with plastic
mallet to work it out of gear case.
NOTE: Retainer flange extends into transmission
case and is a snug fit.
Fig. 17 PULLER COLLAR
1-JAWS
2 - COLLAR
Fig. 18 PULLER ASSEMBLY
1 - COLLAR
2-JAWS
3 - BOLT
4 - WRENCH
5 - MAINSHAFT
6 - PULLER FLANGE
Fig. 19 FIFTH GEAR BEARING PLATE, SHIMS AND
BEARING CUP
1 - MAINSHAFT REAR BEARING CUP
2 - BEARING SHIMS
3 - BEARING PLATE
4 - FIFTH GEAR
Fig. 20 FRONT BEARING RETAINER
1 - DRIVE GEAR
2 - FRONT BEARING RETAINER
DRMANUAL TRANSMISSION - NV4500 21 - 49
MANUAL TRANSMISSION - NV4500 (Continued)

(8) Remove countershaft rear bearing with Puller
Flange 6444-1 and Puller Rods 6444-4 (Fig. 37).
NOTE: Shaft cannot be removed from case until
rear bearing has been removed.
(9) Position first Jaw 6449 on bearing cone and
seat puller flange in notch of puller.
(10) Install second Jaw 6449 on bearing and in
notch of puller flange. Slide Collar 6444-8 over puller
jaws to hold them in place.
NOTE: Retaining collar has small lip on one end
and only fits one way over jaws.
(11) Install Puller 6444 on puller rods, then secure
puller to rods with retaining nuts.Tighten puller bolt
to remove bearing from shaft.
NOTE: If bearing is exceptionally tight, tap end of
puller bolt with copper mallet to help loosen bear-
ing.
(12) Remove bearing puller tools then rotate coun-
tershaft out of gear case (Fig. 38).
(13) Remove countershaft front bearing, with
Puller Flange 6444-1 and Puller Bolts 6444-4 (Fig.
39).
(14) Position first Jaw 6451 on bearing and seat
puller flange in notch of puller jaw.
(15) Install second Jaw 6451 on bearing and in
notch of puller flange. Slide Collar 6444-8 over puller
jaws to hold them in place.
NOTE: Retaining collar has small lip on one end
and only fits one way over jaws.(16) Install puller bridge and bolt assembly 6444
on puller bolts and install retaining nuts. Tighten
puller bolt to remove bearing from shaft.
NOTE: If bearing is exceptionally tight, tap end of
puller bolt with mallet to help loosen bearing.
(17) Remove bearing puller tools.
Fig. 37 COUNTERSHAFT REAR BEARING
1 - COLLAR
2-JAWS
3 - PULLER
4 - WRENCH
Fig. 38 COUNTERSHAFT AND CASE
1 - COUNTERSHAFT
Fig. 39 Countershaft Front Bearing
1-JAWS
2 - COLLAR
3 - PULLER
4 - FLANGE
21 - 54 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)

GEAR CASE
(1) Remove countershaft front bearing cap with
hammer (Fig. 40).
(2) Remove countershaft front bearing cup with
Remover 6454 and Handle C-4171 (Fig. 41).(3) Remove roll pin that secures shift lug on shift
rail in case (Fig. 42). A small pin punch can be mod-
ified by putting a slight bend in it to drive pin com-
pletely out of shift rail (Fig. 42).
(4) Remove shift lug rail.
Fig. 40 COUNTERSHAFT FRONT BEARING CAP
1 - HAMMER
2 - BEARING CAP
Fig. 41 COUNTERSHAFT FRONT BEARING CUP
1 - REMOVER
2 - HANDLE
Fig. 42 SHIFT LUG ROLL PIN
1 - PUNCH
2 - 30É BEND
3 - PIN PUNCH MODIFICATION
4 - SHIFT LUG
5 - SHIFT RAIL
DRMANUAL TRANSMISSION - NV4500 21 - 55
MANUAL TRANSMISSION - NV4500 (Continued)

(18) Remove mainshaft rear bearing, with Puller
Flange 6444-1 and Puller Rods 6444-3 for 4X2 or
6444-4 for 4X4.
(19) Position the first Jaw 6445 on the bearing
cone and seat Puller Flange 6444-1 in notch of jaw
(Fig. 57).
(20) Install second Jaw 6445 on the bearing cone
and puller flange. Slide Collar 6444-8 over jaws to
hold them in place.
(21) Install Puller 6444 on the puller rods and
secure with nuts (Fig. 58). Tighten puller bolt to the
remove bearing.
Fig. 57 MAINSHAFT REAR BEARING PULLER
1 - REAR BEARING
2 - FLANGE
3-JAW
4 - COLLAR5 - MAINSHAFT
6 - PULLER
7 - RODS
8-JAW
21 - 60 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)

(4) Remove countershaft rear bearing plate.
(5) Install a end play shim that will provide mini-
mum countershaft end play. Position shim on rear
bearing cup (Fig. 76).
(6) Install countershaft rear bearing plate (Fig.
73).
NOTE: Verify plate is seated in reverse idler shaft
notch and end play shims are still in position
before installing bolts.
(7) Apply 1-2 drops Mopar Loc N' Seal or equiva-
lent to threads of rear bearing plate bolts. Then
install and tighten bearing plate bolts to 23 N´m (200
in. lbs.).
SHIFT LUG AND RAIL
(1) Lubricate shift lug and rail with CastroltSyn-
torq or equivalent.
(2) Insert shift lug rail part way into case.
(3) Install shift lug on rail.
(4) Position shift rail so roll pin notches are
toward outside of case (Fig. 77).
(5) Install roll pin that secures lug to rail (Fig. 77).
MAINSHAFT AND GEARTRAIN
CAUTION: The reverse, 1-2 and 3-4 synchro compo-
nents can be assembled and installed incorrectly.
Follow assembly procedures for component identi-
fication and location.
Lubricate mainshaft bearing surfaces and all bear-
ing assemblies with CastroltSyntorq or with petro-
leum jelly.(1) Install first snap ring in rear most groove of
mainshaft hub (Fig. 78). This snap ring locates first
gear clutch gear on shaft.
NOTE: Four of these snap rings are used to secure
various components on the mainshaft 1-2 synchro
hub. The snap rings are all the same size and are
interchangeable.
Fig. 76 COUNTERSHAFT END PLAY SHIM
1 - REAR BEARING CUP
2 - END PLAY SHIM (SELECTIVE)Fig. 77 SHIFT LUG AND RAIL
1 - NOTCHES (FOR 5TH GEAR SHIFT FORK ROLL PINS)
2 - LUG RAIL
3 - ROLL PIN HOLE
4 - SHIFT LUG
Fig. 78 FIRST GEAR BEARING AND SNAP RING
1 - SNAP RING
2 - FIRST GEAR BEARING
3 - MAINSHAFT SYNCHRO HUB
21 - 66 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)

(2) Install first gear clutch cone on mainshaft 1-2
synchro hub with recessed side of cone facing front
(Fig. 79). Verify cone is seated against snap ring on
hub.
(3) Install snap ring on mainshaft 1-2 synchro hub
to secure clutch cone (Fig. 80). Verify snap ring is
seated in hub groove and against clutch cone.
(4) Support mainshaft in upright position to install
remaining gears, snap rings and synchro compo-
nents. Shaft can be supported in gear case or hole
can be cut in workbench to support shaft.
(5) If 1-2 synchro hub and sleeve were disassem-
bled for service, reassemble hub, sleeve, struts and
springs as follows:(a) Align and install sleeve on hub. Rotate sleeve
until it slides onto hub. Sleeve only fits one way
and will easily slide onto hub when long slot in
sleeve, aligns with long shoulder on hub (Fig. 81).
(b)
Place wood blocks under hub that will raise hub
about 3.5 cm (1.375 in.) above surface of workbench.
Then allow sleeve to drop down on hub (Fig. 82).
(c)Install springs and struts in hub (Fig. 82). Use
lots of petroleum jelly to hold them in place. Then
compress struts with your fingers and move sleeve
upward until struts are started in sleeve. Verify that
struts are engaged in sleeve before proceeding.
(d) Turn synchro assembly upright. Then move
sleeve into neutral position on hub and work struts
into sleeve at same time. Be sure struts are seated
and springs are not displaced during assembly.
Fig. 79 FIRST GEAR CLUTCH CONE
1 - MAINSHAFT 1-2 SYNCHRO HUB
2 - FIRST GEAR CLUTCH CONE
Fig. 80 FIRST GEAR CLUTCH CONE SNAP RING
1 - FIRST GEAR CLUTCH CONE
2 - MAINSHAFT 1-2 SYNCHRO HUB
3 - CLUTCH CONE SNAP RING
Fig. 81 1-2 SYNCHRO SLEEVE ON HUB
1 - ALIGN WIDE SLOT IN SLEEVE WITH WIDE SPLINE OF HUB
2 - 1-2 SLEEVE AND HUB
Fig. 82 1-2 SYNCHRO STRUTS AND SPRINGS
1 - WOOD BLOCKS
2 - HUB
3 - SLEEVE
4 - STRUTS AND SPRINGS (4 EACH)
DRMANUAL TRANSMISSION - NV4500 21 - 67
MANUAL TRANSMISSION - NV4500 (Continued)