When changing the diameter of tires on a vehicle the final gear ratio needs to be changed as well and 5.29s are currently the largest option available. We selected Yukon Gears for their quality and reputation. They are made in the USA.

A differential locker engages both axle shafts so that they spin as one. Normally an open differential will send the torque needed to turn the wheels to the tire with the least amount of traction, which is good for turning in a parking lot, but not very effective off road. ARB Air Lockers use an air compressor to engage and disengage the locker. ARB Lockers are made in Australia.

The factory transfer case in a Toyota Tacoma is electronically controlled and engaged by a switch on the dashboard. This switch has 3 positions for 2WD High, 4WD High, and 4WD Low. A separate 4WD ECU relays signals from the 4WD switch to actuators in the transfer case and the front differential. By replacing the electronic Tacoma transfer case with the manual FJ version and replacing the front diff actuator with the solid, always engaged version from the AWD FJ cruiser the 4WD system becomes much more robust and reliable because two common failure points are removed. T A C 0 5 can now engage 4WD fully manually with no electronics in the system. The FJ transfer case was further modified with "twin sticks" allowing independent control of low/high and 2WD/4WD engagement. As an example of this benefit, with the front lockers engaged steering is difficult, by momentarily disengaging 4WD, you can stay in low gear, and gain control of steering again.

The factory low range 4WD is good for off road and light crawling, but a Crawl Box takes things to the next level by multiplying your final crawl ratio. In this case that is 4.70 for a final crawl ratio of 255:1. This significantly reduces the output speed to a "crawl" while increasing the torque output. Combined with front and rear lockers the truck literally walks over almost any obstacle. The crawl box can be engaged and disengaged independently of the main transfer case, allowing the factory low plus the on demand option of double low. The second transfer case is supported by an additional fabricated cross member from TMR Customs. The Trail Gear Crawl Boxes are built in the USA.

With the addition of an extra transfer case, the crawl box, the main transfer case must be relocated. This requires rerouting the exhaust, additional cross members, skid plate modifications, and custom length front and rear driveshafts. Since these shafts will be under extreme angles based on the long travel suspension, double cardans were used, which means there are two universal joints. This allows for reduced vibrations and extreme angles. Tom Woods drive shafts are made to order in the USA.

RCLT HD Lower Control Arms are 2.75" wider than stock, which increases the potential wheel travel, but requires longer CV axle shafts. RCV Ultimate CV Axles are made from chromoly steel and support up to 40" tires. RCV axle shafts are made to order in the USA.