Specifications

95
1987 & newer jeeps - np series transfer case
REAR DRIVESHAFT:
When converting to a new transmission, driveshaft modifications are normally necessary. Jeeps with the NP231 now have the
advantage of gaining needed length for suspension travel. We offer a new short shaft “Fixed Yoke” kit, P/N 50-7906, that will
add 4” of rear driveshaft length on a YJ, and up to 6” on a TJ. This kit has the provision for the vacuum shift control located on the
stock tailhousing (mainly found in Cherokees). This kit comes with a new 1310 C.V. yoke. If you would like to use a non-C.V. yoke
like a 1350, we offer kit P/N 50-7907 that allows a couple of yoke options which are listed below.
The Jeep NP231 is one of the most commonly used transfer cases today. It is a chain-driven, planetary designed gear box with
a low ratio of 2.72 to 1. For the average 4-wheeler, this is a good transfer case. One of the biggest faults of this transfer case is
the overall length. At 20+ inches, this creates an extremely short rear driveshaft in the Jeep YJ & TJ Wranglers. This short rear driveline
becomes even more crucial when the vehicle is lifted or a transmission swap is performed. In addition, when a lift kit is installed,
larger tires are usually the next upgrade. Strength and driveline angle of the output shaft then becomes a concern.
To make the NP231 better suited for these upgrades, we have designed our “Fixed Yoke” kit with the
best features available. We manufacture a new one-piece tailhousing that will add the needed inches
to your rear driveline length. This will allow you to obtain a better driveshaft angle and eliminate
driveline vibrations. The new 32 spline output shaft is over 50% stronger than stock.
This kit, along with a new 1310 series C.V. yoke, makes the NP231 a better transfer case
for trail use. A full set of installation instructions is provided to assist in the installation
of this kit.
The installation of this kit requires you to nearly disassemble the entire transfer case. If your
transfer case is in need of a rebuild, now is the perfect time to do it.
Our kit P/N 50-7907 allows the use of a couple different yokes. The yoke options are as follows:
P/N 716295 - 1310 Non-C.V. Yoke (ONE YOKE, NO CHARGE WITH PURCHASE OF THIS KIT)
P/N 300472 - 1350 Non-C.V. Yoke U-Bolt Style (ONE YOKE, NO CHARGE WITH PURCHASE OF THIS KIT)
P/N 300470 - 1310-1350 C.V. & Non-C.V. Yoke Flange Yoke ($100.00 ADDITIONAL COST)
P/N 300471 - 1410 Non-C.V. Yoke Flange Yoke ($100.00 ADDITIONAL COST)
If your stock NP231 is giving you trouble, we also offer a stock replacement NP231 with or without a heavy-duty short shaft kit
installed.
P/N 29-2310 - NP231 with a H.D. Output Shaft Kit
ATLAS TRANSFER CASE REPLACING A NEW PROCESS:
The Atlas has been designed to fit as a universal transfer case. When replacing a New Process transfer case and retaining your
stock transmission, the Atlas will bolt directly to the stock transmission adapter. The crossmember
mount is always located on this adapter housing. No other adapters will be necessary.
When replacing a New Process transfer case & changing the transmission, we offer numerous
transmission-to-transfer case adapters to mate these units. Because of the wide selection of
input shaft splines, some applications will only require the adapter housing, not a full transfer
case adapter kit. All of the adapter housings we manufacture have provisions for the rubber
crossmember support.