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The Mythological Atlas Transfer Case

Posted in Product Reviews on April 10, 2014
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Not many 4x4 products withstand the test of time and survive unchallenged for long. Oftentimes when a good idea comes along it is eventually knocked off, and before you know it a low-dollar imported alternative hits the market or the market is flooded by competition. One unusual item we’ve seen survive the test of time over the past few years is the Atlas transfer case from Advance Adapters.

Now, the Atlas has seen its share of competitors, but unlike the axle market, winch market, or the overabundant off-road lighting market, few have withstood the storm of competition like the Atlas has. Maybe this is due to the fact that most Atlas transfer cases are hidden up above a skidplate out of sight of most other people on the trail. In fact, like the iconic Hi-Lift Jack and the mythological man-god the Atlas is named after, the Atlas has held onto its market niche almost single-handedly.

The original Atlas transfer case was referred to as the Peanut from its obvious shape. The original low range was 3.5:1.

The story of the Atlas is like any other product, starting with an outside-the-(gear)box idea that seemed a bit farfetched originally but which has since become a staple of our recreation. We’re not saying there are more Atlas transfer cases than there are stock OEM cases such as the Dana 300, NP205, or Roc-Trac NVG241 on the trail, but quite a few have made it to the trail head and underneath almost every imaginable custom 4x4 (Advance Adapters estimates 18,000 built since the start of the Atlas in 1995).

So why would you want an Atlas if your 4x4 already has a perfectly good transfer case in its belly? We headed to Advance Adapter’s Paso Robles, California, headquarters to find out why, check out some original prototypes, and get a behind-the-scenes look at how and why the case is changing, along with possibly some insight into what is coming next.

Atlas 2 Q&A
We started our visit by running some questions by Advance Adapters’ president, Mike Partridge, about the history of the Atlas. Here’s what the company told us:

4WOR: When was the first Atlas built?

Advance Adapters: Late 1995.

4WOR: Whose idea was it to build the Atlas transfer case?

AA: An engineer that knew my father had designed a transfer case (similar to the Dana 300) for the Ford Courier as a conversion to 4x4 and wanted to sell it to us. We (Advance Adapters) thought it might be a good upgrade from the Dana 300 and the price was right. The concept of the Atlas was started then, but not much of the tooling or design of the Ford box was used.

4WOR: What was the reasoning behind developing an aftermarket transfer case?

AA: We thought that there might be a market from the Dana 300 and even more so for the then-popular Jeep YJ market. As word got out that we were working on a gearbox, so did the ideas to make it with some of the early options that were offered.

4WOR: Was there some other commercial demand for an aftermarket transfer case, or were you building it solely for the off-road recreational industry?

AA: It was strictly recreational interest originally.

4WOR: How many prototype Atlases were made before you went into production?

AA: A total of five prototypes were made of the first design, and around seven of the second design. No idea how many we did on the third design.

4WOR: What was the first low-range gear ratio available?

AA: 3.503:1.

4WOR: How many gear ratios are available now?

AA: Six two-speeds and five four-speeds.

4WOR: What low-range gear ratios are currently available?

AA: 1.5/2.0/3.0/3.8/4.3/5.0, but then these are multiplied when used in a four-speed case option.

4WOR: When you first offered the Atlas transfer case, was it an instant hit?

AA: It was accepted and well liked in the industry pretty fast, but the name recognition took a couple years.

4WOR: Do you remember who bought the very first Atlas?

AA: Not sure who bought the first one; I do know Pat Gremillion from Premier Power Welders was one of the first vehicles to run a prototype unit.

4WOR: What made sales of the Atlas transfer case really take off? Motorsports? Recreational wheeling? Other?

AA: It was a combination of all these. The recreational wheeling took off about the time we released the Atlas, then the motorsports picked up the last few years. We are always seeing new markets popping up that keep the Atlas growing.

4WOR: Why should someone buy an Atlas instead of using a stock transfer case?

AA: It does depend on the vehicle to the selling points. Most applications you would get a lower gear ratio, 2WD low ratio with easy shift-on-the-fly 4WD. A Stronger case, larger shaft, yoke options, clocking options, front drive shaft clearances on right, and the ability for a front drive low range only, which can really assist in off-road maneuvering.

4WOR: How many Atlases do you think you’ve made over the years?

AA: Around 18,000.

4WOR: The four-speed Atlas is very popular but it seems at one point there was rumors that some had issues. What were those issues, and have they all been fixed?

AA: Yes, it had issues and yes, it has been fixed. The problem was the four-speed was designed as a multiple low-range gearbox for the underpowered engines. Like the Toyota pickups with the 22R, they doubled the gearboxes getting some extreme low gears, allowing the pickups to increase tire size and get the power to the wheels by increasing the rpm. The Atlas four-speed was built in the same manner for the Jeep four-cylinders and the Jeep JKs with the V-6. The problem came in when the customers with the V-8 and the 50-inch-plus tires. The unit wasn’t designed for that type of application, and then the King of the Hammers–style buggies wanted them, and that was when we pulled it and redesigned the unit. Today it is built to handle the increase of power; however, we still really think it should be used more for the underpowered applications. On the original design we tried to keep it as short as possible to fit as many applications as possible. Today it is longer, but that is for the large mid-plate support bearing that adds strength to the unit.

4WOR: What are some unusual applications for the Atlas transfer case?

AA: Military, commercial, foreign 4x4 buses, farming applications, Coffin mover trailer. It has also been used in filming several movies. They like the front-wheel-drive-only option. One was used on a float in the Rose bowl parade.

4WOR: If the Atlas is called the Atlas 2, was there an Atlas 1?

AA: That was the second prototype; we produced around 70 of them. The application worked fine in all the applications until we tried fitting it into a Jeep YJ with a Torqueflite. The front yoke of the Atlas hit the pan of the transmission, and there was no workaround other than building a new wider case (Atlas 2). The good thing is we also made things a bit wider as to the gears at that time, which is a good thing now. There have been many upgrades since we changed to the Atlas 2, but the name has remained.

4WOR: Are there any plans for an even bigger or stronger Atlas? An iron transfer case or a larger case in general?

AA: We have kicked the idea around for a bigger unit for some of the larger vehicles that the GVW does not work well with the Atlas. We can design and build one, but we just need the demand to support the development and product expense. For the majority of off-roaders, our current Atlas is sufficient, but with enough demand or possibly a large commercial interest/order, we would consider moving forward with a bigger version.

4WOR: That Atlas transfer case seems to be able to take a lot of abuse, but is there a limit to what you recommend for an Atlas?

AA: We keep making improvements to increase its capacity, so it’s hard to say or to put an exact number on this, and it also depends on what the Atlas is going to be used in and how much is 2WD and how much in 4WD. Of course, anything can be destroyed with excessive abuse, but we constantly strive to learn and improve the Atlas. Maintenance, installation, and driving style must all be considered, as well as the rest of the vehicle components. These are all factors to the success or failure of each unit.

4WOR: What do you think people need to know about the Atlas that they don’t?

AA: The Atlas is a great product that has a great reputation. Most people know someone who has one, and that is why they want one themselves. The only thing I can think is that we are always looking for ways to improve on our products. We try to listen to our customers’ feedback for improvements. That’s why the Atlas is successful and that’s why it is a great product.

PhotosView Slideshow


Advance Adapters
Paso Robles, CA 93446

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