Page 1769 of 2627

(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)
Page 1770 of 2627

(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)
Page 1771 of 2627
(6) Install first gear stop ring in 1-2 synchro hub
and sleeve (Fig. 83). Verify stop ring is seated and
engaged in hub and sleeve.
(7) Install 1-2 synchro assembly and stop ring on
mainshaft with the taper on the sleeve facing for-
ward. (Fig. 84).(8) Install snap ring that secures 1-2 synchro on
mainshaft hub (Fig. 85). Verify snap ring is seated in
groove in mainshaft hub.
(9) Assemble second gear clutch cone, clutch ring
and stop ring (Fig. 86).
Fig. 83 FIRST GEAR STOP RING IN SYNCHRO HUB
Fig. 84 1-2 SYNCHRO
1 - MAINSHAFT HUB
2 - 1-2 SYNCHRO ASSEMBLY
3 - TAPERED SIDE OF SLEEVE
Fig. 85 1-2 SYNCHRO SNAP RING
1 - SYNCHRO SNAP RING
2 - 1-2 SYNCHRO ASSEMBLY
3 - MAINSHAFT HUB
Fig. 86 SECOND GEAR CLUTCH CONE, CLUTCH
RING AND STOP RING
1 - STOP RING
2 - CLUTCH RING
3 - CLUTCH CONE
21 - 68 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
Page 1772 of 2627

(10) Install assembled second gear clutch cone and
rings on mainshaft and in 1-2 synchro hub (Fig. 87).
(11) Install snap ring that secures second gear
clutch cone on mainshaft (Fig. 88). Use narrow blade
screwdriver to work snap ring into hub groove as
shown. Verify snap ring is seated in mainshaft
groove.
NOTE: If snap ring will not fit in groove, clutch cone
is slightly misaligned.(12) Install second gear bearing on mainshaft (Fig.
89).
(13) Install second gear on mainshaft and bearing.
Rotate gear until tabs of second gear clutch ring are
seated in tab slots in gear (Fig. 90).
Fig. 87 SECOND GEAR CLUTCH CONE, CLUTCH
RING AND STOP RING
1 - CLUTCH CONE
2 - STOP RING
3 - CLUTCH RING
Fig. 88 SECOND GEAR CLUTCH CONE SNAP RING
1 - SCREWDRIVER
2 - MAINSHAFT HUB
3 - SNAP RING
4 - SECOND GEAR CLUTCH CONE
Fig. 89 SECOND GEAR BEARING
1 - SECOND GEAR BEARING
Fig. 90 SECOND GEAR
1 - SECOND GEAR
2 - CLUTCH RING TABS
3 - TAB SLOTS (IN GEAR)
DRMANUAL TRANSMISSION - NV4500 21 - 69
MANUAL TRANSMISSION - NV4500 (Continued)
Page 1773 of 2627

(14) Install thrust washer pin in shaft (Fig. 91).
(15) Install second gear thrust washer. Verify
washer is seated on gear and pin (Fig. 92).
(16) Install second gear thrust washer snap ring
(Fig. 93). Verify snap ring is seated in mainshaft
groove.
(17) Install third gear bearing spacer on shaft and
seat it against thrust washer snap ring (Fig. 93).
(18) Install third gear bearing on mainshaft (Fig.
94). Bearing should be flush with mainshaft hub.
NOTE: If bearing is not flush with hub, the bearing
spacer or snap ring was not installed.
(19) Install third gear over bearing and onto main-
shaft (Fig. 95).
Fig. 91 THRUST WASHER PIN
1 - THRUST WASHER PIN
2 - SECOND GEAR
Fig. 92 SECOND GEAR THRUST WASHER
1 - SECOND GEAR
2 - SECOND GEAR THRUST WASHER
3 - LOCATING PIN IN WASHER NOTCH
Fig. 93 SNAP RING AND THIRD
1 - SECOND GEAR THRUST WASHER
2 - THRUST WASHER SNAP RING
3 - THIRD GEAR BEARING SPACER
Fig. 94 THIRD GEAR BEARING
1 - THIRD GEAR BEARING
Fig. 95 THIRD GEAR
1 - THIRD GEAR
21 - 70 MANUAL TRANSMISSION - NV4500DR
MANUAL TRANSMISSION - NV4500 (Continued)
Page 1774 of 2627

(20) Install synchro stop ring on third gear (Fig.
96). Verify stop ring is seated on cone taper.
(21) If 3-4 synchro was disassembled for service,
reassemble synchro components as follows:
(a) Align and install synchro sleeve on hub (Fig.
97).Front side of hub has a narrow groove
machined in it.
(b) Insert all three synchro struts in slots
machined in sleeve and hub (Fig. 97).
(c) Install and seat synchro springs (Fig. 97).
Use screwdriver to compress springs and seat them
in struts and hub as shown.(22) Start 3-4 synchro assembly on mainshaft with
the hub groove and sleeve groove both facing for-
ward. Tap assembly onto shaft splines until hub is
about 3 mm (0.125 in.) away from third gear stop
ring. Then align stop ring with synchro sleeve and
hub and seat synchro assembly with Installer C-4040
(Fig. 98).
(23) Verify 3-4 synchro hub is seated on shaft with
approximately 3 mm (0.125 in.) of shaft spline visi-
ble.
NOTE: If hub is not seated, stop ring lugs are mis-
aligned. Rotate ring until lugs are engaged in 3-4
hub slots.
(24) Verify that second and third gear rotate freely
at this point. If not, determine the cause and correct.
(25) Invert mainshaft in case or bench.
(26) Install first gear bearing on mainshaft.
(27) Install first gear on shaft with clutch hub side
of gear facing the front of shaft (Fig. 99). Verify tabs
on clutch ring are aligned and seated in first gear
hub.
NOTE: 1-2 synchro hub will not seat properly if
clutch ring tabs are misaligned.
Fig. 96 THIRD GEAR STOP RING
1 - SYNCHRO STOP RING
2 - THIRD GEAR
Fig. 97 SYNCHRO ASSEMBLY (3-4)
1 - STRUT (3)
2 - SPRING (3)
3 - 3-4 SLEEVE
4 - 3-4 HUB
Fig. 98 SEATING 3-4 SYNCHRO ASSEMBLY ON
MAINSHAFT
1 - 3-4 SYNCHRO HUB
2 - HUB GROOVE
3 - INSTALLER C-4040
DRMANUAL TRANSMISSION - NV4500 21 - 71
MANUAL TRANSMISSION - NV4500 (Continued)
Page 1775 of 2627

(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)
Page 1776 of 2627

(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)