Parts for the

New Process 231 Transfer Case

The New Process / New Venture 231 transfer case is one of the most durable and rebuildable transfer cases in the history of Jeeps.

Master Rebuild Kits

NP231 Rebuild kit for early and late version transfer cases


Our master rebuild kit has been assembled for our customer's rebuilds as well as our own. It is hands-down the most complete kit we've seen anywhere and features all the consumable and wear item components.

Included in the 231 master kit is the chain, which we do not consider to be an optional rebuild item like so many others do. This is the highest grade chain available.


All kits include all the bearings, seals, gaskets, small parts, chain, magnet, oil filter, boot, shift lever bushing, thread locker compound, RTV sealant, face studs and instruction guide (not all items shown in image).

Kit 231MR-1, master rebuild, NP231 transfer case, 1987-1993 versions

Kit 231MR-2, master rebuild, NP231 transfer case, 1994-2006 versions

Applications & Compatibility

NP231 Versions

NP231's are consistent from 1988-1993. Beginning in the 1994 model year, New Venture changed the front input bearing from a wide version to a narrow version. By 1995, the change-over was complete, but individuals with 1994 model year transfer cases can't always be certain of which bearing their transfer case may actually have, unless they pull the front bearing retainer or even fully disassemble the NP231 and check this input gear bearing.

  • The early NP231 uses a BD50-8 bearing, measuring 24mm wide
  • The later NP231 uses a 6010-N bearing, measuring 16mm wide


The earlier style input gear, left, has a wide bearing journal. The later style input gear, right, has a narrow bearing journal.

For a more in-depth discussion of these versions, see this page.

Related Products

Slip Yoke Eliminator for NP231 Transfer Cases
NP231 2 low kit
NP231 transfer case main shaft

Other Components

Essentially all parts for the 231 are available new and affordably so. For anything not shown, contact us.

Installation Requirements

It is very common for our customers to do top-level rebuild work, using good methods and by following our included instruction guide. We suggest the rebuilder have access to a set of snap ring pliers, and a small arbor press, in addition to standard shop tools.

Turn Key, Master Rebuilt 231 Transfer Case

231 Transfer Case Rebuilt

Our NP231 is professionally and meticulously rebuilt. We use the best components, including bearings, bushings, seals and gaskets built by our Dana 18 specialists and experts. All known updates and improvements are performed. Put the experience of thousands of Dana transfer case rebuilds to work for your Jeep.

Because of the variations involved and shipping options available, we encourage you to contact us directly by phone or e-mail. We will help you put together the transfer case which best fits your requirements.

Note that we can supply a core NP231 or we can arrange to have yours sent in with a core credit of $300. Transfer cases are built to order and typically take 1-3 weeks to ship. Contact us for current build times. Costs range from $988.+, depending on your configuration, ranging from standard versions to SYE options, HD chains, etc.


your transfer case package is palleted and wrapped (if trucking is required) or packaged in a double-wall box (if by parcel), fully insured and ready to bolt into your application. Novak will seek the best competitive shipping rates with our extensive trucking networks. It will arrive at a location of your choosing, though we strongly recommend a business location with a dock / forklift for delivery (if trucking), as residential and liftgate fees can add up to an extra $100. per delivery.

Also See