Christian Hazel
Brand Manager, Four Wheeler
Pull up a chair, son, 'cause have we got a story for you. If you're sick of the wimpy stock gearing in your Jeep, believe us when we say you don't have to have a 100-inch wheelbase to run Advance Adapter's slick dual low range 4 Speed Atlas T-case. We added a 10.34:1 unit to a '97 Wrangler and actually gained an inch of driveshaft length. But we should back up a bit.
A couple years ago Advance Adapters took its exceptionally durable and versatile Atlas II, machined the case a bit, and added a low range planetary gearbox with a 2.72:1 gear reduction to the front. Behind this planetary, Advance Adapters stuffs the compact Atlas II T-case with either 2.0:1 or 3.8:1 low range gearing. That means you can have 1:1, 2.0:1, 2.72:1, and 5.44:1; or 1:1 2.72:2, 3.8:1, and 10.34:1. The result is brute strength, three shifters, and a gear for any occasion. And it's all in a package that's almost an inch shorter than a standard NP231 T-case equipped with a slip yoke eliminator.
For the installation, we leaned on TAG Motorsports in Escondido, California, because the shop is no stranger to modifying Jeeps and 4x4s. Shop foreman Jay Miller served up his '97 TJ as test fodder. Since Advance Adapters includes detailed, step-by-step instructions we'll only skim the highlights. But be sure to check out our sidebar, "Crawling Time" to see just what these crazy-low crawl numbers mean in the real-world.
Crawling Time
You can talk about super-low range gearing all day long, citing its increased benefits in control, finesse, and capability in certain off-road situations. But what does that equate to in the real world? To illustrate, we set up cones 100-feet apart and recorded the time it took to drive the course at 2,000rpm with the Jeep's AX-15 in First gear (3.83:1). The Jeep runs 4.88 axle gears for a final Low range of 193.25:1.
