Dodge RAM TRUCK 1500 1995 Service Manual page 1307

21 - 24 if3500 MANUAL TRANSMISSION
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CORRECT POSITION
IS MARKED ON
SLEEVE
J9421-56
Fig. 56 Location Of Position Marks On 1 -2 Synchro
Sieeve
Fifth-Reverse Synchro Position
The fifth-reverse synchro hub has raised shoulders
on one side of the spline bore. This side of the hub
must face the rear of the output shaft after installa­
tion.
The fifth-reverse sleeve has a large taper on one
side. Be sure the sleeve is installed so the taper faces
toward front of the output shaft.
Synchro Component Assembly
The easiest method of assembling each synchro is
to install the springs, struts and detent balls one at a
time as follows:
(1) Slide the sleeve part way onto the hub. Leave
enough room to install the spring in the hub and the
strut in the hub groove.
(2) Install the first spring in the hub. Then install
a strut over the spring. Be sure the spring is seated
in the spring bore in the strut.
(3) Slide the sleeve onto the hub just far enough to
hold the first strut and spring in place.
(4) Place the detent ball in the top of the strut.
Then carefully work the sleeve over the ball to hold
stallation. However, if both hub sides are the same,
the hub can be installed in either direction.
The 3-4 synchro sleeve has grooves machined on
one side. Be sure this side also faces the front of the
output shaft.
1-2 Synchro Position
The 1-2 synchro hub has raised shoulders on one
side of the spline bore. This side of the hub must face
the rear of the output shaft after installation.
The top surface of the 1-2 synchro sleeve is marked
for correct installation (Fig. 56). One side of the
sleeve is marked "first gear side". Be sure this side is
facing the first gear after installation.
TRANSMISSION ASSEMBLY
Assembly Information
Gaskets are not used in the NV3500 transmission.
Sealers are used at all flange joints. Recommended
sealers are Mopar Gasket Maker (or Loctite 518) for
all flange joints and Loctite Ultra, heavy body sili­
cone (black) sealer (or Mopar equivalent) for the in­
put shaft bearing retainer. Apply these products as
indicated in the reassembly procedures.
It is very important that the transmission
shift components be in Neutral position during
assembly. This is necessary to prevent damag­
ing synchro and shift components when the
housings are installed.
Transmission gears, shafts, and synchro compo­
nents should all be lubricated with recommended
gear lubricant during assembly operations. Petro­
leum jelly can be used to prelubricate bearings and
to hold parts in place during assembly. Only petro­
leum jelly should be used. Do not use chassis or
bearing grease. This type of heavy grease will
plug oil channels in the housings and gears re­
sulting in failure.
The 3-4, 1-2 and fifth-reverse synchro hub snap
rings can be fitted selectively. New snap rings are
available in 0.05 mm (0.0019 in.) thickness incre­
ments. Use the thickest snap ring that will fit in
each snap ring groove.
Proper reassembly of the NV3500 requires some
special service tools. Geartrain Assembly Fixture
6747 is especially important. The entire geartrain
and shift mechanism must be assembled in this fix­
ture before either transmission housing can be prop­
erly installed. The tools are needed to avoid
damaging the gears, housing, or shift components.
CORRECT ASSEMBLY OF SYNCHRONIZER
COMPONENTS
The synchronizer sleeves, hubs and struts are dif­
ferent and must be kept in sets. Only the synchro de­
tent balls and springs are interchangeable.
The 3-4 and 1-2 synchro rings are all made of cast
metal and are interchangeable. However, the reverse
gear synchro ring is made of solid brass and must
not be interchanged.
A total of three detent springs, struts and balls are
used in all three synchro assemblies. The balls and
springs are interchangeable.
The synchro sleeves and hubs must also be cor­
rectly positioned on the shaft in order to operate
properly. Assemble and install each synchro accord­
ing to the following instructions.
3-4 Synchro Position
Some 3-4 synchro hubs may have a raised shoulder
on one side of the spline bore. If so, this side of the
hub must face the front of the output shaft after in-