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Jeep Liberty Transfer Case Tech - Low, Low Liberty

Posted in How To on September 12, 2006
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Photographers: Jordan May
The Jeep Liberty 4x4 can become an ultimate 'crawler with the addition of a Klune-V Extreme Underdrive. A built JB Conversions NP231 transfer case completes this ultimate off-road package.

We've seen many Klune-equipped vehicles on the trail over the years and have always been impressed with their performance. There's typically plenty of slow going but not a lot of stopping because the Klune literally climbs its way over most anything. After a careful look at the viable transfer case swaps and related upgrade parts for an '02 Jeep Liberty 4x4, we came to the conclusion that if mated to the right transfer case, a Klune-V would be an awesome addition.

The Klune-V Extreme Underdrive multiples existing gear reduction to achieve an insanely low crawl ratio. Thanks to its built-in clocking ring that offers threaded holes for studs around its perimeter, the Klune-V will bolt up to most transfer cases and only adds minimal length to the rear driveline (just 7 inches if an adapter isn't required). The unit can be mounted in any position and used for a wide variety of applications. Adding to its versatility, the Klune-V unit features two shifter-mounting locations in case one is rendered unusable due to the clocking position. The other location can be used as an inspection cover if it is still accessible after installation. A cable shifter is included with the Klune-V and includes an ample length of cable for multiple shifter-mounting possibilities. A direct-shift kit is also available. Two models of the Klune-V Extreme Underdrive are available to choose from: the 2.7:1 planetary-geared Goliath unit and the 4:1 double-compound, planetary-geared David. We employed a David unit to get that ultra-low Klune-V experience.

The Klune-V and upgraded "JB231" are a good fit under this '02 Liberty. Stout driveshafts from J.E. Reel complete the conversion.

Though the unit would easily bolt to the factory-installed NV242 transfer case in the '02 Jeep Liberty 4x4, we elected to seek a more trail-proven transfer case that benefits from greater aftermarket support. An NP231J 'case from a Jeep TJ was chosen and subjected to a complete rebuild using every available JB Conversions' NP231 upgrade in the book ("NP231 Forever," Oct. '06). We still maintained the 2.72:1 Low ratio, however, since the Klune-V will provide more than ample reduction. Mated together, the Klune-V and NP231 will offer four gear ranges to choose from: a 4WD High range (Klune disengaged, T-case in High), a 4WD 2.72:1 Low range (Klune disengaged, T-case in Low), a 4:1 crawl range (Klune engaged, T-case in High), and an extreme-Low reduction range (Klune engaged, T-case in Low). All told, a whopping 243:1 overall reduction was achieved with the installation of these components.

PhotosView Slideshow
PhotosView Slideshow
Using the Klune-V universal footing mount bolted between the reduction housing and the transfer case, Chris welded an extension onto the crossmember and then secured it to the footing mount using a Scout transmission mount.

To carry out the Klune-V and NP231 conversion, we sought out the assistance of Chris Johnson at Rock-Tech Offroad in La Habra, California. Chris was primarily a Scout guy when we first met him, but he's been letting Jeeps in the door for the last few years and has had pretty good success at it. The entire conversion was completed in a little over a day's time, and we've been pleased with the results. On the road, there's no additional gear noise since the Klune-V only turns when it's engaged, but on the trail we're reaching new heights with ultra-low gearing for the toughest off-road driving situations.

NumbersYou can calculate the overall reduction provided by the Klune-V in the same manner in which you calculate your crawl ratio - by multiplying your ratios. In our case, we'll multiply the Klune ratio (4) by the T-case (2.72) by the trans First gear ratio (6; note that ratio is actually 3.0:1, but the torque converter in auto transmissions has built-in gearing that can multiply ratios by 1.5 to 2 times, e.g. 3x2=6) by the axle gear ratio (3.73). With the help of a calculator we came up with a 243:1 overall reduction.

Klune-V David: 4:1NP231J transfer case Low: 2.72:145RFE First gear: 3.0:1 (x2)Axle gear ratio: 3.73

Formula:Klune-V ratio x NP231 ratio x trans First gear ratio x axle gear ratio = Overall reduction

Or:4 x 2.72 x 6 x 3.73 = 243

Overall reduction is 243:1

PhotosView Slideshow


JB Conversions
Sulphur, LA 70664
J.E. Reel Drive Line Specialists

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