Advance Adapters 50-4702 User Manual
Page 2
GM TRUCK 4 SPEED MODEL SM465 TO
JEEP & SCOUT DANA 18/20 (Spud Design)
ADVANCE ADAPTERS INC.
P/N: 50-4702
P.O. Box 247, 4320 Aerotech Center Way
Old Part No: 711047NS-6
Paso Robles, CA 93447
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Telephone: (800) 350-2223
Fax: (805) 238-4201
Page Rev. Date:
12-20-00
SPECIAL NOTE:
The components packaged in this kit have been assembled and machined for specific type of conversions. Modifications to any of the
components will void any possible warranty or return privileges. If you do not fully understand modifications or changes that will be required to complete your conversion,
we strongly recommend that you contact our sales department for more information. This instruction sheet is only to be used for the assembly of Advance Adapter
components. We recommend that a service manual pertaining to your vehicle be obtained for specific torque values, wiring diagrams and other related equipment.
These manuals are normally available at automotive dealerships and parts stores.
GM & CHEVY SM465 4 SPEEDS 1968 & UP:
This transmission can be identified by a case length of 12". The casting numbers on the case should be GM465452, 6273212
or 3901127. The top shift cover casting number should be GM3901131. The P.T.O. opening is available on both sides
of the main case. This transmission has a non-synchro first gear. The gear ratios for this transmission are as follows:
First Gear
6.46
Second Gear
3.58
Third Gear
1.70
Fourth Gear
Direct
Reverse
6.09
In order to use this transmission with the Advance Adapter kits, you must make sure that you have the proper output shaft
from the original 4 speed transmission to couple to the new adapter. Currently, we manufacture the adapters for both 35
spline and 10 spline output shafts. If you transmission has a 32 spline output shaft, then you will be required to change
to the other designs listed. The correct transmissions which are not compatible are 1981 and up four wheel drive K1, K2.
The four wheel drive K3 models are equipped with a 10 spline output shaft that can be used with our kits. The part numbers
for the new shaft, if required, are as follows:
GM Part No. 6259663
-
Output shaft with 10 splines
GM Part No. 3932265
-
Output shaft with 35 splines
The shaft has a rear bearing that is retained with either a snap ring or special lock nut. Without this snap ring or lock nut
in the proper position, the shaft will walk forward into the input shaft causing severe damage. Make sure that the shaft
is locked by either the lock nut or snap ring to avoid severe damage.
The new spud shaft that we have furnished with your kit must slip over the output shaft without bottoming out or causing
spline interference. The spud shaft is located in the correct position by using the bearing that is counted on the back side
of the new adapter. With the spud shaft in position and the adapter on the new transmission, you must be able to rotate
the shaft freely There are certain applications that may require a slight grinding of the original output shaft to prevent the
original shaft from bottoming out inside our new coupler. On transmissions having 35 splines, the threaded portion at the
very end of the shaft will need to be removed. This can be done with an abrasive cutoff saw and must be done for clearance
inside the new adapter coupler.
The adapter plate that we have furnished for your new transmission has a special pocket that has been machined into the
transmission side for clearance over the reverse counter shaft. Make sure that the counter shaft in the transmission is
rotated for proper engagement into the new adapter housing.
The right side of the main case will need to be ground off for clearance of the front output yoke on certain installations.
We recommend a trial fit with your transfer case and front output yoke so that any modifications that may be required can
be done before final installation. This is a good time to set up the shifter linkage for the transfer case controls. Make sure
that the adapter fits flush against the back of the transmission and indexes properly over the two bearings.
This adapter housing has two holes that will need to be plugged with the two set screws provided. Thread Lock or RTV
blue silicone is recommended when installing the set screws to prevent leakage. These castings are designed for Toyota
Land Cruisers and Jeep applications. You will only plug the holes on Jeep applications.