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    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

    Features

    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.

    Contents

    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).

    NP231 Rebuild kit for early and late version transfer cases
    231MR-1
    NP231 Rebuild kit for early and late version transfer cases
    231MR-2

    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.

    231_input_short_wide231_input_short_narrow

    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

    Heavy Duty Slip Yoke Eliminators for 231 Transfer Cases

    Upgrade and shorten your NP231 output shaft to handle the increased torque of your new gears, and improve the driveshaft angle, especially important for lifted Jeeps. View the SYE kit that will work best for your situation.

    Shifter Kits for New Process Transfer Cases

    As this combination will frequently be paired with Jeep New Process chain drive transfer cases (NP231, NP242), this shifter kit will make the conversion go not just smoother, but will improve your shifting action and reliability significantly over factory. Read about them here.

    NP231 2 low kit

    Kit 2204000, 2-Low shift sector, w/range fork for LOW231

    TeraFlex's 2Low kit will give you true low range gearing without eliminating the ability of the front to freely turn. This kit is purely internal, and requires no external modification. The shift pattern for your transfer case will be 2H > 4H >N >4L > 2L.
    These kits are only compatible with the 231-J transfer cases.

    2204000
    NP231 transfer case main shaft

    Shaft, main, NP231 transfer case, 1987-1995 with large hub journal, 16”, good used version

    The NP231 is surprisingly strong in nearly all areas, but occasionally, the output portion of the Jeep 26 spline to break under shock loading or other high-torque conditions. These factory mainshafts are good used units pulled from transfer cases that have come across our benches for slip-yoke-elimininator kits. They have been hand selected, inspected and are in great condition to bring a factory style 231 back into the game. Several other versions available. Contact us.

    83503141

    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. Checkout our prices here: Rebuild Services

    Logistics

    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