1993 DODGE TRUCK Service Repair Manual

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Fig. 46 Removing Shift Lug Roii Pin Fig. 4?
Removing
Shift Lug Rali
Fig. 48 Removing Shift Lug Rail Bushings Fig. 49 Gear Case Magnet Location chro components can be installed backwards.
To avoid reassembly problems, mark the speed
gears,
clutch gears, synchro hubs, and sleeves
for reference during teardown. Use paint or a scriber for marking purposes.
Then
stack the
geartrain parts in
order
of removal. This prac­
tice
will
help avoid incorrect assembly and lost

time.

(1) Remove drive gear thrust bearing from end of
mainshaft, if not previously removed.
(2) Remove fourth gear synchro struts and springs
from 3-4 hub and sleeve (Fig. 50). Three struts and springs are used. Keep springs and struts together
for inspection and cleaning. Store parts in a paper
cup to avoid losing them.
Fig. 50 3-4 Synchro Strut And Spring Removal
(3) Remove 3-4 sleeve from 3-4 synchro hub (Fig.

51).

(4) Remove 3-4 synchro hub from mainshaft
splines with suitable size bearing splitter, or with
two tapered drifts. Position splitter or drifts between third gear stop ring to start moving hub off shaft.
Then complete hub removal by tapping it off shaft with plastic mallet. Tap hub at 6-8 different points to
remove hub evenly.
MAINSHAFT
DISASSEMBLY
Not all of the mainshaft gear and synchro com­
ponents are a one-way fit. Some gear and syn-

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J922M19

Fig.
51
Removing
3-4
Sieeve
From Hub
THIRD

GEAR

NEEDLE

BEARING

ASSEMBLIES

THIRD
GEAR

THIRD
GEAR STOP

RING
J922M21

Fig.
53 Third Gear Needle Bearing
Removal
SECOND
GEAR
THRUST
WASHER

THRUST

WASHER

SNAP
RING

THIRD
GEAR
BEARING
SPACER
3-4

SYNCHRO
HUB
J9221-122

Fig.
54 Bearing
Spacer
And
Snap
Ring
Location
SECOND
GEAR
J922M20

Fig.
52 Third Gear,
Stop
Ring
And 3-4 Hub
Removal
(5) Remove 3-4 synchro hub, third gear stop ring
and third gear (Fig. 52). (6) Remove third gear bearing assemblies from
mainshaft (Fig. 53). (7) Remove third gear bearing spacer (Fig. 54).
(8) Remove snap ring that retains second gear
thrust washer on mainshaft (Fig. 54). (9) Remove second gear thrust washer (Fig. 55).
Note that washer is notched for locating pin.
THRUST

WASHER

SECOND GEAR

BEARING
J9221-123

Fig.
55
Second
Gear Thrust
Washer
Removal

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Fig.
56
Second
Gear
Removal

Fig.
57
Second
Gear Bearing
Removal

Fig.
58 Thrust
Washer
Locating Pin
Removal
(10) Remove second gear (Fig. 56).
(11) Remove second gear bearing assembly (Fig.

57).
•

J922M27

Fig.
59
Removing
Second
Speed
Clutch
Gear
Snap
Ring

Fig.
60
Second
Speed
Clutch
Gear,
Clutch
Ring
And
Stop
Ring
Removal
(13) Remove snap ring that retains second speed
clutch gear (Fig. 59). Snap ring is seated in main-
shaft synchro hub groove. (14) Remove second speed clutch gear, synchro
clutch ring and synchro stop ring (Fig. 60).
(15) Remove 1-2 synchro hub snap ring (Fig. 61).
(16) Mark position of 1-2 synchro sleeve and hub
for assembly reference. Side of hub with flat hub spring goes toward front (Fig. 62). Note that tapered side of sleeve also goes toward front.
(17) Remove 1-2 synchro sleeve, hub, struts and
springs as an assembly (Fig. 62). It is not necessary
to disassemble synchro components unless worn, or damaged.
(18) Remove first gear synchro stop ring and
clutch ring (Fig. 63).
(19) Remove first speed clutch gear front snap ring
from mainshaft hub (Fig. 64). (20) Remove first speed clutch gear (Fig. 65). (12) Remove thrust washer locating pin (Fig. 58).
Use needle nose pliers to grip and remove pin.

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J9221-129

Fig. 81 Hemming 1-2 Sleeve And Hub Snap Ring 1-2

SLEEVE

AND
HUB
(MARK

POSITION
FOR
ASSEMBLY

REFERENCE)

HUB
SPRING
J9221-130

Fig. 62 Removing 1-2 Synchro Sleeve And Hub

FIRST
GEAR

CLUTCH
RING

FIRST
GEAR
STOP
RING
J922M31

Fig.
63 First Gear
Stop
And
Clutch
Ring
Removal

(21) Remove first speed clutch gear rear snap ring
from mainshaft hub (Fig, 65). It is not really neces­ sary to remove this snap ring unless it, or the main-shaft is to be replaced.

(22)
Remove mainshaft rear bearing as follows:
FIRST

SPEED

CLUTCH
GEAR
CLUTCH

GEAR

SNAP
RING

(FRONT)

J922M32

Fig.
64 First
Speed
Clutch
Gear Front
Snap Ring
Removal

CLUTCH GEAR

SNAP
RING (REAR) FIRST

SPEED

CLUTCH
GEAR
J9221-133

Fig.
65 First
Speed
Clutch
Gear
Removal

(a) Assemble Puller Flange 6444-1 and Puller
Rods 6444-3 (Fig. 66).
(b) Position first Puller Jaw 6445 on bearing
cone (Fig. 66).
(c) Seat Puller Flange 6444-1 in notch of first
puller jaw (Fig. 66).
(d) Install second Puller Jaw 6445 on bearing
cone and on puller flange (Fig. 66).
(e) Slide Retaining Collar 6444-8 over puller
jaws to hold them in place (Fig. 67). Note that re­ taining collar has small lip on one end and only
fits one way over jaws.
(f) Install Puller 6444 on puller rods. Then se­
cure puller to rods with retaining nuts (Fig. 67).
(g) Place holding wrench on hex at top of puller
(Fig. 67). Then tighten puller bolt with adjustable
wrench to remove bearing from shaft (Fig. 67). If
bearing proves difficult to remove, tap end of puller bolt with copper hammer after each turn of bolt.
This will help loosen bearing on shaft and ease re­ moval.

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TRANSMISSION OVERHAUL

•
Fig. 66 Assembling

SPECIAL

Fig. 67 Removing Mainshaft Rear Bearing (23) Remove bearing puller tools.
(24) Remove reverse gear thrust washer (Fig. 68). (25) Remove reverse gear thrust washer locating
pin (Fig. 69). Rear Bearing Puller Tools
REVERSE

GEAR

J922M35
Fig. 68 Reverse Gear Thrust Washer Removal (26) Remove reverse gear and synchro components
as assembly (Fig. 70). It is not necessary to re­
move or disassemble synchro components unless they are damaged and need to be replaced. If synchro sleeve or struts require service, mark
position of sleeve on hub before removal. Cor­
rect sleeve position is important as sleeve can be
installed backwards causing shift problems.
(27) Remove reverse gear bearing assembly from
mainshaft (Fig. 70).

•

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Fig.
69
Removing
Thrust Washer Locating Pin (28) Remove reverse gear synchro stop ring and
clutch gear (Fig. 70).
FIRST
REVERSE

Fig.
70
Reverse
Gear, Bearing And
Stop
Ring
Removal
(29) Remove reverse gear bearing spacer from
mainshaft (Fig. 71). (30) Remove first gear snap ring (Fig. 71). Tension
of this snap ring is considerable. Heavy duty snap
ring pliers will be required to spread the ring far enough to remove it.
(31) Remove reverse clutch gear (Fig. 72).
(32) Remove first gear from bearing and mainshaft
(Fig. 73).
(33) Remove first gear bearing from mainshaft
(Fig. 74).

TRANSMISSION
CLEANING AND INSPECTION
Clean the gears, bearings shafts, extension/adapter
housing and gear case with solvent. Dry all parts ex­ cept the bearings with compressed air. Allow the
bearings to either air dry or wipe them dry with clean shop towels.
Fig.
71
Reverse
Gear Bearing
Spacer
And First Gear

Snap
Ring
Removal

J922M51

Fig.
72
Removing
Reverse
Clutch
Gear
FIRST

GEAR
J922M52

Fig.
73
Removing
First Gear
Inspect the reverse idler gear, bearings, shaft and
thrust washers (Fig. 75). Replace the bearings if the
rollers are worn, chipped, cracked, flat-spotted, or

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•

MAINSHAFT FIRST
SPACER SHAFT J9221-183 Fig.
75
Reverse
idler
Components
brinnelled. Or if the bearing cage is damaged or dis­
torted. Replace the thrust washers if cracked,
chipped, or worn. Replace the gear if the teeth are
chipped, cracked or worn thin.
Inspect the drive gear and bearings (Fig. 76). Mi­
nor scratches and burrs on the gear surfaces can be
reduced with an oil stone and 400 grit paper wetted
with oil. Replace either bearing if worn, or damaged.
Replace the gear if any teeth, splines, or bearing sur­
faces are also worn or damaged.
Inspect the front bearing retainer and bearing cup
(Fig. 77). Replace the bearing cup if scored, cracked,
brinnelled, or rough. Check the release bearing slide surface of the retainer carefully. Minor corrosion, nicks,
or pitting can be smoothed with 400 grit emery and pol­
ished out with crocus cloth. Wet the abrasive paper and
crocus cloth with oil when smoothing/polishing. Replace
the retainer if worn or damaged in any way. Inspect the countershaft and bearings (Fig. 78). Re­
place the bearings if worn, rough, flat spotted, or
heat checked. Check the countershaft gear teeth carefully. Small nicks, scratches, or burrs can be re-
MAINSHAFT FRONT
DRIVE GEAR J9221-181
Fig.
76 Drive Gear
Components

BEARING
OIL
FRONT BEARING CUP SEAL RETAINER
Fig.
77 Front Bearing Retainer
Components

REAR COUNTERSHAFT FRONT J922M84
Fig.
78 Countershaft And
Bearings

moved with an oif stone and 400 grit paper wetted
with oil. However, replace the shaft as an assembly if the forward gear is loose, or any of the teeth are
worn, cracked, broken, or severely chipped.
Be sure to check condition of the countershaft bearing

cups.
Replace either bearings cup if worn, or damaged.

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TRANSMISSION OVERHAUL
21 - 23
Check condition of the mainshaft. Inspect all the
bearing surfaces, splines and threads. Also check condi­ tion of the snap ring grooves in the hub area and the speedometer drive gear teeth (Fig. 79). Minor scratches
or burrs can be removed with an oil stone and polished
with crocus cloth. However, replace the shaft if any sur­ faces exhibit considerable wear or damage.
GEAR
CASE
BEARING

SURFACES HUB
BEARING
NUT

SURFACES THREADS SPEEDOMETER

TEETH

SPLINES SPLINES SPLINES

J922M85

Fig.
79 Mainshaft Bearing And
Spline
Surfaces
Check condition of the gear case and extension or
adapter housing (Fig. 80). Be sure the alignment dowels
in the case top surface and in the housing/adapter are
tight and in good condition.
Run a tap through the gear case bolt holes if the
threads need minor cleanup. Helicoil inserts can be used to repair seriously damaged threaded holes if nec­
essary.
Be sure all case and housing/adapter sealing and
mating surfaces are free of burrs and nicks. This is especially important as gaskets are not used in the
NV4500. Minor nicks and scratches on the sealing surfaces can be dressed off with a fine tooth file or oil
stone.
Replace the gear case or housing/adapter if cracked
or broken. Do not attempt to repair this type of dam­ age by welding or brazing.
Check condition of the countershaft fifth gear com­
ponents (Fig. 81). This includes the shift lug and rail located in the gear case and the rail bushings.
Inspect the gear and hub assembly. Minor burrs can
be cleaned up with an oil stone. However, the gear and hub assembly should be replaced if the teeth or splines are excessively worn, or damaged. The synchro sleeve
should also be replaced if worn or damaged in any way.
Do not reuse synchro struts that are worn, or springs
that are collapsed or severely distorted. Replace worn distorted synchro parts to avoid shift problems after as­
sembly and installation.
The shift fork should be inspected for evidence of
wear and distortion. Check fit of the sleeve in the
fork to be sure the two parts fit and work smoothly.
Replace the fork if the roll pin holes are worn over-
EXTENSION

HOUSING

(2-WHEEL
DRIVE)

ADAPTER

HOUSING
(4-WHEEL
DRIVE)
J9221-186

Fig.
80 Gear
Case
And Extension/Adapter
Housings
size or damaged. Do not attempt to salvage a worn
fork. It will cause shift problems later on. Replace
the shift fork roll pins if necessary, or if doubt exists about their condition.
The bearings should be examined carefully for wear,
roughness, flat spots, pitting, or other damage. Replace
the bearings if necessary.
Inspect the stop ring and clutch gear, replace ei­
ther part if worn or damaged in any way. Also be sure replacement parts fit properly before proceeding
with assembly.
Inspect the 1-2 synchro components (Fig. 82). The hub
weights and retainer springs are reusable if in good condition. However, replace the springs if distorted, or
broken and replace the weights if worn or damaged. Examine the hub and sleeve for wear or damage.
Replace the sleeve and hub if the splines are worn,
chipped or damaged. Replace the synchro struts if worn, or chipped. Also
replace the springs if collapsed, distorted, or broken. Inspect the mainshaft geartrain components (Fig.

83).
Check the teeth on all gears, hubs, clutch gears,
stop rings and clutch rings. The teeth must be in
good condition and not worn, cracked, or chipped. Re­
place any component that exhibits wear or damage. Examine the synchro stop rings, clutch rings and
clutch gears. Replace any part that exhibits wear,
distortion, or damage. Replace the clutch rings if the
friction material is burned, flaking off, or worn. Inspect all of the thrust washers and locating pins.
Replace the pins if bent, or worn. Replace the wash­ ers if worn, or the locating pin notches are distorted. Check condition of the synchro struts and springs.
Replace these parts if worn, cracked, or distorted.