What is np231j?

Published by Anaya Cole on

What is np231j?

It’s found under a multitude of Jeeps (Wranglers and Cherokees), Dodge, and Chevy 4x4s. It’s a chain-driven transfer case with an aluminum housing and a 2.72:1 gear ratio (though these three traits are common with many transfer cases built today).

What Jeeps have a NP231?

Since 1988, the NP231 has been the “Command Trac” transfer case used in the XJ Cherokee, MJ Comanche, and YJ Wrangler. It has been the “Command Trac” transfer case in the ZJ Grand Cherokee since its introduction.

How do I know what transfer case my Jeep has?

The easiest way to identify the transfer case input is by identifying the stock transmission that Jeep used. The 21 and 23 splined output shafts vary on different transmission models. The AX15 transmission is always 23 spline shaft and extends 1/2″ beyond the face of the transmission.

Can NP231 be flat towed?

When your NP231 is in “N”, both the front and rear driveshafts are still locked together, but the transfer case is disconnected from the transmission input. This shouldn’t cause any issues when flat towing, unless you have a front lunchbox locker. This was changed in the TJ models of the NP231 – it has a true neutral.

Which jeeps have 2 speed transfer cases?

Two different transfer cases were used, the NV247 in 1999-2004 WJs and the NV245 in 2005-2010 WKs and 2006-2009 XKs. For the 1999-2004 Jeep Grand Cherokees using the NV247 transfer case, in “4-All Time” mode torque is applied to only the rear wheels under normal driving conditions.

Can you flat tow an XJ?

To flat tow an XJ you need to put the Trans in Park and the Tcase in Neutral. Leave the wheel unlocked as well. If the XJ is in decent shape, then flat towing it shouldn’t be much of an issue.

Can a Jeep XJ be flat towed?

The Jeep Cherokee can be flat towed as long as the trim being considered has the ActiveDrive II/2- speed Power Transfer Unit.

What Jeeps had the 242 transfer case?

The 242 premiered in the XJ Cherokee / Wagoneer and MJ Commache as the SelecTrac option. It was used in the 1991-1998 ZJ Grand Cherokee. The 242 persisted throughout the full run of XJ Cherokees and continued on in the 2002 KJ Liberty.

What’s the Jeep NP231 transfer case output?

The 231 has a driver’s side front output and centerline rear output. The NP231 features two ranges; a low range gear that is a respectable 2.72-to-1 (the lowest of all the Jeep transfer cases with the exception of the NP241OR) and a direct-drive in high range.

What are the specs of a jeep NP231?

The NP231 features two ranges; a low range gear that is a respectable 2.72-to-1 (the lowest of all the Jeep transfer cases with the exception of the NP241OR) and a direct-drive in high range. It features three modes; two-wheel-drive, four-wheel-drive and neutral – for a factory combination of 2H, 4H, N, 4L.

Does the NP231 have a neutral disconnect?

Early NP231’s on Jeeps with a vacuum front axle disconnect feature (as is usually evident by the presence of a vacuum switch on the NP231) did not have a true neutral disconnect when shifted into neutral. The front and rear yokes remained connected.

Are NP231 speedometer gears interchangeable?

NP231 speedometer gears are interchangeable to correct for tire size and axle ratio changes. See this page to learn more about this. The 231 appears to have reached the end of its main production in Jeeps in 2006. However, expect it to be well supported by the aftermarket for decades to come.