Advance Adapters 50-4801 - Manual (Page 2)

GM TRUCK 4 SP. 2WD MODEL SM465 35 SPL.
TO JEEP & SCOUT DANA 18/20 (Spud Design)
ADVANCE ADAPTERS INC. P/N: 50-4801
P.O. Box 247, 4320 Aerotech Center Way Old Part No: 711048-6
Paso Robles, CA 93447 PAGE 2 OF 3
Telephone: (800) 350-2223 Fax: (805) 238-4201 Page Rev. Date: 05-13-03
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 6.56
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 your transmission has a 31 spline output shaft, then you will be required to change
to the other designs listed. The correct transmission can be found in all 2WD vehicles, 1968 -88. The 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 output shaft is held into place by the transmission output yoke and nut. When using this kit, the nut and yoke are
removed. To retain the output shaft from moving back and forth in the transmission, we've included a set collar to hold
the output shaft in the proper position in reference to the rear output bearing and transmission case. The set collar should
fit snug up against the rear output bearing and then locked into position.
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 mounted 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. The threaded area of the stock output shaft must be removed for use with the Advance Adapters coupler.
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.