Twin-stick transfer cases are hold-outs from an earlier era when off-road trucks were more akin to tractors than automobiles, and offered a level of versatility unmatched by any single-stick case. A twin-stick transfer case give the driver complete control over the truck's drive; with one quick flick he can convert the truck from a low-geared rock crawler to a high-speed rear driver, and even into front wheel drive for certain situations.
Identify the front and rear axle sticks. Dodge and GM use the passenger-side stick to control the rear axle, and driver's side for the front. Ford transfer cases are the other way around.
Identify the shift pattern. For almost all transfer cases you'll push the lever forward for the direct drive ("High") gear range, put it in the middle for neutral, and pull it back for low range.
Lock your front axle hubs by turning the ridge in the middle of the hubs one half turn clockwise. Some makes may use a counter-clockwise or quarter-turn arrangement.
Put the truck into rear-wheel drive high range by putting the front-axle stick in neutral and pushing the rear-stick forward. Engage four wheel drive high by pushing the front-stick forward.
Put the truck into two rear-wheel drive low by coming to a complete stop, putting the front-stick into neutral and pulling the rear-stick all the way back. Engage four-wheel drive low by pulling the front-stick back at any time. Do not use too much pressure when engaging the front axle's low gear; if you hear any sort of grinding, ease up on the stick.
