Specifications

1941-79 jeep & scout transfer cases
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A. MB Jeep Universals 1941-1945: The Dana Spicer transfer case, Model MB dual lever shift control, can be identified by
the small intermediate gear idler shaft that is only .750" in diameter. This MB transfer case is marginal for V8 power, so we suggest
that you limit your engine size to a V6 or change the transfer case to the later model Dana 18. This transfer case uses an input gear
with 1-3/8" 6 spline. We offer a special Saturn overdrive unit for use with this transfer case.
Transfer Case Input Gear #A10469 (18-8-19) 27 tooth x 6 spline
B. Jeep Universals 1945-1979: These vehicles were equipped with the Dana Spicer Model 18 and 20. These transfer
cases have a four position shifter that provides two gear ratios in 4WD, one ratio in 2WD, and a neutral position. Four wheel drive
low provides a reduction ratio of 2.03:1 on the Dana 20, and a 2.46:1 on the Dana 18. The controls varied from a dual lever design
to a single lever on the later models. The bolt pattern on the input side has always remained the same, so transfer cases can be
interchanged between years - with some exceptions. These exceptions include: the indexing or alignment bearing retainer that
protrudes from the back side of the transmission. The early models used a 3.150" indexing diameter, while the later model transfer
cases used a hub that measured 4.000". The other critical area is that the input gears have different splines and tooth counts. This
can be critical especially when changing transmissions that require a different input gear. This is real common with vehicles
equipped with a AMC factory TH400 and Dana 20 transfer case when changing over to the Advance Adapters design kit. Our design
uses a standard input gear with either 6, 10 or 23 splines, while the factory adapter design uses a 15 tooth gear and a snap ring
for locking the gear in position. Another difference is that the Model 20 transfer cases have the power to the rear axle directly in line
with the transmission, while the Dana 18 has the power offset to the passenger side.
TRANSFER CASE INPUT GEAR INFORMATION
Dana 20 Transfer Case - 26 Tooth x 6 Spline #946574 (18-8-46)
Dana 20 Transfer Case - 26 Tooth x 10 Spline #947339 (18-8-49) Early Jeeps
Dana 20 Transfer Case - 26 Tooth x 23 Spline
Dana 18 Transfer Case - 29 Tooth x 6 Spline #809297
Dana 18 Transfer Case - 29 Tooth x 10 Spline #947382
Dana Spicer 18/20 Transfer Case 6 Spline: On all Jeep vehicles 1941-79 equipped with the Dana Spicer 6 spline transfer
case, you will have the largest selection available for transfer case adapters. These adapters are for replacement of Jeep
transmissions that have a 6 spline input gear to the transfer case. The Jeep transmission model numbers are T84, T90, T86,
T85, T89, T98A, T18, T15, and T150. Not all of the transmission options are compatible for use with short wheel base vehicles.
Dana Spicer 18/20 Transfer Case 10 Spline: On all Jeep vehicles 1969-71 equipped with the Dana Spicer 10 spline
transfer case, you will have a large selection of transfer case adapters that can be used without changing the input gear of the
transfer case. These adapters are all manufactured to fit a 10 spline transfer case input gear that was used only on T14 3 speed
transmissions. The adapters that have the 10 spline design are critical when your vehicle is equipped with a Warn, Husky, or
Saturn overdrive. If your vehicle does not have an overdrive, then you could use any of the 6 spline adapters and simply change
the input gear of the transfer case to one that had 6 splines. Refer to the gear numbers listed above for the proper gear. All
of the adapters will require a new output bearing, P/N 716302, and a T86 bearing retainer, P/N 716001.
Dana Spicer 20 Transfer Case 15 Spline: On all Jeep vehicles that were equipped with
the AMC TH400 automatic transmission, you will find that they used a special input gear to the
transfer case that was held in place with a snap ring and splined to a special coupler shaft with
15 teeth. We manufacture a replacement adapter for this stock application, Part No. 50-0500.
The individual components of this kit will not work with your stock adapter components.
If you are using this adapter on a new installation, you will need to purchase a new input
gear to the transfer case.
Scouts With Dana 300 1979-80: In 1979, the International Scout vehicles were
equipped with a specially designed Dana 300 transfer case. This particular transfer
case resembled the Jeep Dana 20 design and, in fact, can be directly interchanged with the Jeep Dana 20 transfer case since
they both have the same bolt pattern. The Scouts that were equipped with this transfer case either had the 727 Torqueflite
automatic or T19 4 speed transmission. The input gear to the transfer case could have been either a 23 spline (on automatics),
or a 6 spline (on 4 speed applications). The tooth count on the Scout Dana 300 transfer case is always 26 teeth. Replacement
gears for the Scout Dana 300 are available through Border Auto Parts.