Advance Adapters 50-4703 User Manual
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GM TRUCK 4SPEED MODEL SM465 TO
JEEP 6 SPLINE DANA 18/20
ADVANCE ADAPTERS INC.
P/N: 50-4703
P.O. Box 247, 4320 Aerotech Center Way
New Item: (02/08)
Paso Robles, CA 93447
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Telephone: (800) 350-2223
Fax: (805) 238-4201
Page Rev. Date:
02-25-08
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
Introduction:
This kit fits a majority of Dana 18/20 to SM 465 applications. The new main shaft included in the kit
is manufactured to fit the six spline input gear on both the Dana 18 and Dana 20. Although rare, customers with the
10 spline input gear will have to purchase a new 6 spline input gear (Call for availability). The Dana 18/20 cases were
manufactured with several different shifter styles, because of this each installation may differ slightly. For more
information on stock shifter applications see Page 4.
Preparation For Assembly:
The most difficult part of this installation is replacing the SM465 main shaft. Advance
Adapters highly recommends using a manual transmission shop for this part of the install.
If you attempt the installation on the SM465 shaft on your own, please be careful with the sleeves as they are a press
fit and they can shatter during installation. The sleeves are a very close tolerance. To help in the assembly of these
sleeves, you can heat them in a oven (250 degrees for 10 minutes) which will increase the size of the bushing making
it easier to install. (Be sure to use eye and face protection when pressing, and leather gloves when handling the heated
bushing.)
To start off, make sure you received all parts included in the kit. Also, check to make sure you received the correct
bearing retainer. The Dana 20 uses AA Part# 716001 and Dana 18 uses AA Part# 716002.
Procedure:
1. To make the installation easier, drain the oil out of the transmission and transfer case.
2. Next, install the gasket between the transmission and adapter plate. Gasket sealer will make this step easier by
holding the gasket in place.
3. Then install the adapter plate on the transmission with the eight 3/8”-16 x 1” socket head cap screws. Torque the
bolts to 35 ft./lbs.
4. The adapter plate comes with three clocking positions. When the desired angle has been chosen, install the supplied
set screw studs. There are several different size studs supplied for this step. The 3/8”-16 x 1.25” stud will thread
into the tapped hole of the Dana 18/20 case.
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.