Jeep/Scout Dana 20 / Dana 18
Jeeps had a long run using the Dana-Spicer 18 or 20 transfer case: From 1941 to 1979. These cases all had a right hand drop (front drive shaft on the right, or passenger side of the vehicle).
The Dana 18 can be identified easily, as its rear output is offset down and to the passenger side (directly behind the front output yoke). This makes this case a possible replacement for Toyota Land Cruiser cases, which have the same rear output configuration. The Dana 20 has its rear output yoke directly behind the input, in the center of the vehicle.
Crawler mounted to a Dana 20 with one version of a stock Dana 20 shifter.
Use of the Jeep Dana 20 With the Klune-V Extreme Underdrive:
These transfer cases, although used in different vehicles, all have the same bolt pattern. In terms of bolting to a Klune-V, the only way they differ is in the indexing hole diameter (see below) and the input spline count where the shaft goes into the transfer case input gear.
A Dana 18/20 mating kit PN KV100153 is required to bolt a Klune-V
Extreme Underdrive to these transfer cases. This Kit consists of a
bearing, a seal, a plate which carries the bearing and seal as well as
adapted the bolt patterns, and necessary hardware.
Mating Kit alone: PN KV100153
Mating Kit w/Small hole bearing retainer PN KV100153-90
Mating kit w/large hole bearing retainer
Scout versions used with an automatic transmission: This gear will have a 23 spline configuration. It must be replaced with the Scout gear from the manual trans applications, which will have the correct 6 spline configuration.
Transfer Case Shifter
Use of the original shifter is usually pretty
straight forward. These cases typically came with shifters mounted to the
front of the case. While there are a number of variations, we have not
found any that will not work with the Crawler in place. Unmodified, the
shifter will exit the floorboards to the rear of where it originally came
out. Alternately, the shifter can be modified or a different shifter
installed that will have longer linkage rods and will exit at or near
the stock location.
Transmission Support/Cross Member
The Dana 18/20 adapter is used with the universal
foot mount system. This places the mounting point directly in front of
the transfer case, where it will provide best support for the
transmission-crawler-transfer case setup. The crossmember will need to be
relocated farther back on the frame rails or a new crossmember fabricated,
or in the case of a skid plate, the skid plate drilled further to the rear
to bolt up the mount.