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Transfer Case Knowledge Gateway

To a large degree, Jeeps are what Jeeps are because of their transfer cases. The chances are that your Jeep already has a great transfer case in it. So, read up and discover the details of this critical part of the mix that is your Jeep's powertrain.

The most significant transfer cases include:

Jeep Transfer Cases

The original. The Model 18 is a significant part of history, yet it is still a very relevant transfer case for a great many enthusiasts.

  • 1941-1971 military & civilian Jeeps and IH vehicles
  • Iron case, gear-driven, passenger-side offset drive for front and rear output shafts
  • Tough as nails, compact and easy to service
  • Adaptable to a broad variety of the great transmissions

The offspring of the Dana 18, the Dana 20 was the strong "silent-type" and it put a bit of refinement into 4wd.

  • 1962-1979 Jeep CJ's, FSJ's , IH & Ford
  • Iron case, gear-driven, passenger-side offset drive for the front axle and centered output for the rear axle
  • Even stronger than its predecessor, yet still compact and easy to service
  • Adaptable to a broad variety of the great transmissions

The culmination of Dana's transfer case engineering, the Model 300 was the final coup in gear drive.

  • 1980-1986 Jeep CJ's, and the 1980 IH
  • Iron case, gear-driven, pasenger-side offset drive for the front axle and centered output for the rear axle
  • Slightly stronger than its predecessor with improved gearing and operation. Servicability and durability are premier
  • Adaptable to more transmission options than any other

The surprisingly great Model 231 is ubiquitous, enjoying a long production run and a great success in chain-drive.

  • 1987-2006 Jeep YJ, TJ, XJ, MJ, ZJ as well as GM and Dodge applications
  • Aluminum alloy case, chain-driven, planetary-reduction, driver-side offset drive for the front axle and centered output for the rear axle
  • Tough, with a great low-range and a myriad of aftermarket improvements
  • Adaptable to the full array of excellent transmissions

Jeep clues into the deep gearing craze and releases the Model 241OR RockTrac.

  • 2002-current Jeep TJ / LJ / JK Rubicons
  • Aluminum-Magnesium alloy case, chain-driven, deep planetary-reduction, driver-side offset drive for the front axle and centered output for the rear axle
  • Very tough, with a supreme 4:1 low-range
  • Fully adaptable to a great variety of transmissions

The Model 242 is where things finally start to go well for differential-ed transfer case

  • 2002-current Jeep TJ / LJ / JK Rubicons
  • Aluminum alloy case, chain-driven, planetary-reduction, driver-side offset drive for the front axle and centered output for the rear axle, integrated differential
  • Fairly strong
  • Adaptable to a great variety of transmissions

The QuadraTrac was revolutionary gearbox, though it had a bit of a bumpy ride.

  • 1973-1979 Jeep FSJ & CJ
  • Aluminum alloy case, chain-driven, planetary-reduction, passenger-side offset drive for both front and rear axles
  • Quite strong, yet a bit complicated and requiring attention to chain stretch
  • Rarely retained in powertrain conversions

Chain drive hits the mainstream, if not yet its stride, in these early New Process transfer cases.

  • 1980-1991 Jeep FSJ & early XJ
  • Aluminum alloy case, chain-driven, planetary-reduction, driver-side front offset drive for the front axle and centered rear output
  • Generally strong. Some models have viscous couplings, differentials and vacuum acutation, which take them out of the running for some serious Jeepers
  • Sometimes retained in powertrain conversions and adaptable to many excellent gearboxes

The Model 207 was the springboard for the Model 231. It was generally successful.

  • 1984-1987 Jeep XJ and 1987 YJ
  • Aluminum alloy case, chain-driven, planetary-reduction, driver-side front offset drive for the front axle and centered rear output
  • Tough enough for many situations
  • Adaptable to a good selection of excellent transmissions

Military-grade strength is found in the Model 200, and the Model 200 is found only in the military M715 / M725 trucks.

  • 1966-1971 Kaiser military trucks, and early Dodge militaries from 1947, onward
  • Iron case, gear-driven, passenger-side front output and centered rear output. Divorced mount
  • Outstanding strength
  • Usually retained in conversions with its factory T98, or used with 2wd style transmissions

 

This pending section will cover the Atlas and Stak transfer cases and the Klune reduction box, which are Dana 300 / NP231 flanged inputs, and typically compatible with any transmission that is adaptable to them.