ORIGINAL FACTORY GEARING isn't very low

Have you ever apporached a steep track where the standard Toyota first gear was too high to the point you would loose power and couldn't get it to the top? You simply can't go slow enough to avoid bashing and banging the obstacles. One possible solution is to ride the clutch. This leads to other problems, the obvious being damage to the clutch. When you add taller tires the problem becomes even worse as your ratios are changing from what Toyota had planned them to work at. The key to driving slower is your 4x4's crawl ratio. The lower the ratio the the more control you have over the way your truck responds to the terrain.

ORIGINAL FACTORY GEARING isn't very low. The stock crawl ratio is 39 to 1 (3.93 first gear, 2.28 tcase, 4.37 R&P), too high for rock crawling. Having a crawl ratio down around 90 to 100 to 1 makes life much easier on the rocks and your drivline. One way to do this is to change the transfer case low range gears from 2.28 to 4.70:1. Just changing to these gears would result in a crawl ratio of 80 to 1. The dual setup provides a crawl ratio of 90 to 1 (3.93 first gear, 2.28 first case, 2.28 second case, 4.37 R&P). This new low range gear ratio is 128% lower than a stock setup.

The dual case setup is much more flexible in that it allows for you to run low & high range 2WD, this is also useful for those that run a self locking centre (lockright, detroit) being able to select 2wd low will give you the ability to steer your truck around corners. Now imagine being able to go from Standard low range to double low, imagine how slow your truck will crawl now.

With a 5 speed you get 15 forward gears including the standard low ratio you have now and 3 reverse gears to choose from. The front shifter is simply a high/low shifter (crawler box). High range is 1:1, and Low range is 2.28:1. The rear shifter is the same "J" pattern you have now, with High range as 1:1, and Low range as 2.28:1.

The ultimate is known as the dual ultimate crawler, this combines reduction gears in the rear case and stock 2.28 gears in the forward crawler. This combination results on an over all crawl ratio of 159 to 1 (3.39 first gear, 2.28 forward case, 4.7 rear case, 4.37 R&P). With two transfer cases you have twenty forward gears and 4 different reverse gears.