(28) Install reverse clutch gear on first gear (Fig.
99). Verify clutch gear is seated on shaft splines.
(29) Install reverse clutch gear snap ring with
heavy duty snap ring pliers (Fig. 99). Verify snap
ring is seated in groove.
NOTE: Reverse gear will not fit properly if snap ring
is not seated.
(30) Install stop ring on clutch cone (Fig. 100). Ver-
ify stop ring is seated on cone taper.
(31) Install reverse gear bearing spacer on main-
shaft and seat against reverse clutch gear snap ring
(Fig. 101).
(32) Install reverse gear bearing on mainshaft
(Fig. 101).
(33) If reverse gear sleeve and struts were disas-
sembled for service, reassemble sleeve, struts and
springs as follows:CAUTION: The reverse sleeve will fit either way on
the hub. Verify tapered side of the sleeve faces
rearward.
(a) Position sleeve on hub so tapered side of
sleeve faces rearward. (Fig. 102).
(b) Rotate sleeve to align teeth on sleeve and
hub. Sleeve will slide easily into place on hub when
properly aligned.
(c) Install springs in gear hub (Fig. 102). Use
petroleum jelly to hold springs in place if desired.
Fig. 102 REVERSE GEAR SYNCHRO ASSEMBLY
1 - REVERSE GEAR
2 - SLEEVE
3 - SPRING (3)
4 - STRUT (3)
5 - HUB
Fig. 99 FIRST GEAR AND CLUTCH GEAR
1 - FIRST GEAR
2 - REVERSE CLUTCH GEAR SNAP RING
3 - REVERSE CLUTCH GEAR
Fig. 100 CLUTCH GEAR STOP RING
1 - REVERSE GEAR STOP RING
2 - CLUTCH GEAR
3 - FIRST GEAR
Fig. 101 REVERSE GEAR BEARING AND SPACER
1 - REVERSE GEAR BEARING
2 - BEARING SPACER
3 - FIRST GEAR
21 - 72 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
(d) Compress first spring with flat blade screw-
driver and slide strut into position in hub slot.
Then work spring into seat in strut with small
hooked tool or screwdriver.
(e) Install second and third struts in same man-
ner as described in step (d).
(f) Work sleeve upward on hub until struts are
centered and seated in sleeve. Sleeve should be in
neutral position after seating struts.
(34) Install reverse gear and synchro assembly on
mainshaft (Fig. 103). Rotate assembly until stop ring
lugs engage in hub slots and gear drops into seated
position.
(35) Install reverse gear thrust washer (Fig. 104).
(36) Install rear bearing on mainshaft with
Installer 6446. Seat bearing on output shaft and
against thrust washer (Fig. 105).
(37) Install fourth gear stop ring in 3-4 synchro
sleeve (Fig. 106).
(38) Install fourth gear clutch gear in stop ring
(Fig. 107).
Fig. 103 REVERSE GEAR
1 - REVERSE GEAR AND SYNCHRO ASSEMBLY
Fig. 104 REVERSE GEAR THRUST WASHER
1 - THRUST WASHER
2 - REVERSE GEAR
Fig. 105 MAINSHAFT REAR BEARING
1 - INSTALLER
2 - MAINSHAFT REAR BEARING
Fig. 106 FOURTH GEAR STOP RING
1 - 3-4 SYNCHRO SLEEVE
2 - FOURTH SPEED STOP RING
Fig. 107 FOURTH GEAR CLUTCH GEAR
1 - FOURTH SPEED CLUTCH GEAR
DRMANUAL TRANSMISSION - NV4500 21 - 73
MANUAL TRANSMISSION - NV4500 (Continued)
(39) Roll gear case onto its left side.
(40) Grip mainshaft at pilot bearing hub and just
behind reverse gear. Then lift assembly and guide
rear of shaft through bearing bore at rear of case.
(41) Continue holding front of shaft but switch
grip at rear to shaft output splines. Lift mainshaft
assembly slightly, align gears and seat assembly in
case.
(42) Set transmission case upright (Fig. 108).
(43) Install drive gear thrust bearing on mainshaft
(Fig. 109). Use plenty of petroleum jelly to hold bear-
ing in place.
(44) Check alignment and mesh of mainshaft
gears. If gears are not aligned, roll case on side and
realign shaft and gears in case.DRIVE GEAR AND RETAINER
(1) Install bearing on drive gear with Installer
6448 (Fig. 110).
(2) Lubricate pilot bearing with petroleum jelly
and install it in drive gear bore.
(3) Install drive gear on mainshaft. Work gear
rearward until mainshaft hub is seated in pilot bear-
ing.
(4) Install bearing cup in front retainer with Han-
dle C-4171 and Installer C-4308 (Fig. 111).
Fig. 108 MAINSHAFT AND GEARTRAIN IN CASE
1 - MAINSHAFT AND GEARTRAIN
2 - FOURTH SPEED CLUTCH GEAR
Fig. 109 DRIVE GEAR THRUST BEARING
1 - MAINSHAFT
2 - DRIVE GEAR THRUST BEARING
Fig. 110 FRONT BEARING ON DRIVE GEAR
1 - INSTALLER
2 - BEARING
3 - DRIVE GEAR
Fig. 111 FRONT BEARING CUP IN RETAINER
1 - INSTALLER
2 - HANDLE
3 - WOOD BLOCKS
4 - RETAINER
21 - 74 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
(5) Install new oil seal in front bearing retainer
with Installer 6052 (Fig. 112). Use one or two wood
blocks to support retainer as shown. Lubricate seal
lip with petroleum jelly after installation.
(6) Clean contact surfaces of gear case and front
bearing retainer with a wax and grease remover.
(7) Apply Mopar Silicone Sealer or equivalent to
flange surface of front bearing retainer (Fig. 113).
(8) Install front bearing retainer over drive gear
and start it into case.
(9) Start front bearing retainer in gear case. Verify
retainer lube channel is at the top-center(12
O'clock)position (Fig. 113).(10) Align front bearing retainer bolt holes and tap
retainer into place with plastic mallet. Installnew
retainer bolts and tighten to 30 N´m (22 ft. lbs.) (Fig.
114).
NOTE: Never reuse the old bolts.
MAINSHAFT END PLAY
(1) Install mainshaft rear bearing cup in case and
over bearing. Tap bearing cup into place with plastic
mallet.
(2) Install rear bearing plate to hold mainshaft
and rear bearing in position (Fig. 115).
NOTE: Do not install any end play shims at this
time.
(3) Tighten rear bearing plate bolts securely.
(4) Place gear case in upright position on bench.
Either cut hole in bench to accept drive gear and
front retainer or use C-clamps to secure transmission
on bench.
NOTE: Do not leave transmission unsupported.
(5) Install Extension Rod 8161 into a suitable
threaded hole in rear of case.
(6) Mount dial indicator on extension rod and posi-
tion indicator plunger against end of mainshaft.
(7) Move mainshaft forward to remove all play
then zero dial indicator.
(8) Move mainshaft upward and record dial indica-
tor reading. Move mainshaft with pry tool positioned
between drive gear and case.
(9) End play should be 0.051-0.15 mm (0.002-0.006
in.). Select fit shims are available to adjust end play.
If end play adjustment is required, remove bearing
plate and install necessary shim.
(10) Reinstall rear bearing plate with oil hole in
bearing plate at the top (Fig. 115).
(11) Apply Mopar Lock N' Seal or equivalent to
bearing plate bolt threads. Install and tighten bolts
to 23 N´m (200 in. lbs.).
Fig. 112 BEARING RETAINER OIL SEAL
1 - INSTALLER
2 - RETAINER
3 - WOOD BLOCK
Fig. 113 LOCATION OF FRONT RETAINER LUBE
CHANNEL
1 - LUBE CHANNEL
2 - FRONT RETAINER
3 - APPLY GASKET MAKER HERE
Fig. 114 FRONT BEARING RETAINER
1 - DRIVE GEAR
2 - FRONT BEARING RETAINER
DRMANUAL TRANSMISSION - NV4500 21 - 75
MANUAL TRANSMISSION - NV4500 (Continued)
(12) Install mainshaft fifth gear with Installer
6446 (Fig. 116). Gear is seated when it contacts rear
bearing.
COUNTERSHAFT FIFTH GEAR SYNCHRO
(1) Install thrust washer pin in countershaft (Fig.
117).
(2) Install thrust washer on countershaft. Turn
washer until pin engages in washer notch (Fig. 118).
NOTE: The flat side of washer faces the rear and
cone side faces the front.
(3) Lubricate and install fifth gear bearing on
countershaft (Fig. 119).
Fig. 115 REAR BEARING PLATE
1 - BEARING PLATE OIL HOLE (AT TOP)
2 - MAINSHAFT REAR BEARING PLATE
Fig. 116 MAINSHAFT FIFTH GEAR
1 - MAINSHAFT FIFTH GEAR
2 - INSTALLER
Fig. 117 FIFTH GEAR THRUST WASHER PIN
1 - THRUST WASHER PIN
2 - COUNTERSHAFT
Fig. 118 FIFTH GEAR THRUST WASHER
1 - PIN
2 - THRUST WASHER
Fig. 119 COUNTERSHAFT FIFTH GEAR BEARING
1 - COUNTERSHAFT
2 - FIFTH GEAR NEEDLE BEARING
21 - 76 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
(4) Install synchro sleeve on hub of countershaft
fifth gear with tapered side of sleeve facing front and
the flat side facing rear (Fig. 120).
(5) Install shift fork in synchro sleeve (Fig. 121).(6) Install assembled fifth gear, synchro sleeve and
shift fork (Fig. 122). Align fork with shift lug rail and
align gear with bearings and countershaft. Start
components onto shaft and rail, then tap gear and
fork into place with plastic or rawhide mallet.
(7) Install fifth gear synchro struts and springs
(Fig. 123).
Fig. 120 SYNCHRO SLEEVE ON COUNTERSHAFT
FIFTH
1 - GEAR HUB
2 - SYNCHRO SLEEVE
3 - COUNTERSHAFT FIFTH GEAR
Fig. 121 FIFTH GEAR SHIFT FORK IN SYNCHRO
SLEEVE
1 - SYNCHRO SLEEVE
2 - SHIFT FORK
Fig. 122 COUNTERSHAFT FIFTH GEAR, SHIFT
FORK AND SYNCHRO SLEEVE
1 - SHIFT FORK AND SLEEVE
2 - FIFTH GEAR HUB
3 - SHIFT FORK ROLL PINS
Fig. 123 FIFTH GEAR SYNCHRO STRUTS AND
SPRINGS
1 - FIFTH GEAR HUB
2 - SYNCHRO SPRING (3)
3 - SYNCHRO STRUT (3)
DRMANUAL TRANSMISSION - NV4500 21 - 77
MANUAL TRANSMISSION - NV4500 (Continued)
(8) Assemble and install fifth synchro clutch gear
and stop ring in fifth gear hub (Fig. 124). Verify
parts are seated in fifth gear hub.
(9) Install clutch gear snap ring (Fig. 125).
(10) Align roll pin holes in shift fork with notches
in shift lug rail. Then install roll pins from top side
of fork (Fig. 122).
NOTE: Roll pins only fit one way due to small
shoulder at one end of each pin.
FIFTH GEAR NUT
(1) Install belleville washer onto the mainshaft.
(2) Install fifth gear nut over the mainshaft.
(3) Tighten the clamp bolt until the gap in the
clamp nut assembly is closed.
(4) Back the clamp bolt off one full turn.(5) Place 10-15 drops of Loctite 272 onto the main-
shaft threads where the fifth gear nut will be
engaged.
(6) Install fifth gear nut on mainshaft (Fig. 126).
(7) Hold mainshaft Socket 6993 4X2 or Socket
6984 4X4 while installing the fifth gear nut.
(8) Tighten fifth gear nut as much as possible with
Wrench 6743, long handle ratchet, breaker bar and
applicable socket wrench (Fig. 127).
(9) Lock mainshaft gears by shifting all synchro
sleeves into engaged position.
Fig. 124 FIFTH SYNCHRO CLUTCH GEAR AND
STOP RING
1 - STOP RING
2 - CLUTCH GEAR
Fig. 125 FIFTH SYNCHRO CLUTCH SNAP RING
1 - CLUTCH GEAR RING
2 - FIFTH SYNCHRO CLUTCH GEAR
Fig. 126 FIFTH GEAR NUT
1 - FIFTH GEAR
2 - FIFTH GEAR NUT
Fig. 127 FIFTH GEAR NUT
1 - WRENCH
2 - FIFTH GEAR NUT
3 - SOCKET
21 - 78 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
(10) Tighten fifth gear nut with Nut Wrench 6743
and high capacity torque wrench. Tighten nut to 366-
380 N´m (270-280 ft. lbs.). Have helper hold trans-
mission steady if necessary.
(11) Torque the fifth gear clamp nut clamping bolt
to 13.5 N´m (10 ft. lbs.).
(12) Unlock the mainshaft gears by shifting all
synchro sleeves out of the engaged position.
EXTENSION/ADAPTER HOUSING
(1) Clean mating surfaces of extension/adapter
housing and gear case with a wax and grease
remover.
(2) Check alignment dowels in gear case and hous-
ing or adapter. Be sure dowels are in position and
seated.
(3) Apply Mopar Silicone Sealer or equivalent to
gear case and housing mating surfaces.
(4) Align and install extension/adapter housing on
gear case (Fig. 128).
(5) Apply Mopar Lock N' Seal or equivalent to
threads of extension/adapter housing bolts.
(6) Install and tighten housing bolts to 54 N´m (40
ft. lbs.).SHIFT MECHANISM
(1) Clean mating surfaces of shift cover and gear
case with wax and grease remover.
(2) Apply a small amount of Mopar silicone sealer
or equivalent to sealing surface of shift cover.
CAUTION: Do not over-apply an excesive amount
sealer. Excess can squeezed into gear case and
could block lubricant feed holes in time.
(3) Lubricate synchro sleeves with CastroltSyn-
torq gear lubricant or equivalent. Then apply light
coat of petroleum jelly to shift fork contact surfaces.
(4) Verify shift fork pads (Fig. 129) are secure.
(5) Verify 1-2 and 3-4 synchro sleeves and forks in
shift cover are in neutral position.
(6) Align and seat shift cover on transmission.
NOTE: If cover will not seat, it may not be aligned
on gear case dowels or shift forks are not aligned
with sleeves and shift lug.
(7) Apply Mopar Lock N' Seal or equivalent to
threads of shift cover bolts.
(8) Install shift cover bolts and tighten to 27-31
N´m (216-276 in. lbs.).
(9) Apply sealer to backup lamp switch. Install
switch into cover and tighten to 22-34 N´m (193-265
in. lbs.).
(10) Install vent assembly if removed. Apply an
adhesive/sealer to vent tube to help secure it in cover.
Fig. 128 INSTALLING EXTENSION/ADAPTER
HOUSING
1 - GEAR CASE
2 - EXTENSION HOUSING
Fig. 129 SHIFT FORK PAD
1 - SHIFT FORK PADS
2 - FIFTH-REVERSE FORK
DRMANUAL TRANSMISSION - NV4500 21 - 79
MANUAL TRANSMISSION - NV4500 (Continued)