Transfer Case

GENERAL INFORMATION
The NV 231 is a part-time transfer case with a low range reduction gear mechanism. It is the only transfer case available in this application.

The NV 231 has three operating ranges plus a Neutral position. The reduction gear mechanism consists of a planetary and annulus gear that provide a 2.7:1 reduction ratio when engaged. The annulus gear is fixed in the case; it does not rotate.

The input gear is splined to the transmission output shaft. It drives the mainshaft through the planetary gear and range hub. The front output shaft is operated by a drive chain that connects the shaft to a drive sprocket on the mainshaft. The drive sprocket is engaged/disengaged by the mode fork, which operates the mode sleeve and hub. The sleeve and hub are not equipped with a synchro mechanism for shifting.

The geartrain is mounted in two aluminum case halves attached with bolts. The mainshaft front and rear bearings are mounted in aluminum retainer housings bolted to the case halves.

Fig. 1 Fill/Drain Plug And LD. Tag Locations:

TRANSFER CASE IDENTIFICATION
A circular ID tag is attached to the rear case of each transfer case. The ID tag provides the transfer case model number, assembly number, serial number, and low range ratio.

NOTE: The transfer case serial number also represents the date of build.

OPERATING RANGES
NV 231 operating ranges are:
^ 2-wheel drive high (2H)
^ 4-wheel drive high (4H)
^ 4-wheel drive low (4L)

Two-wheel drive range is for use on all road surfaces. The 4-wheel drive high and low ranges are not for use on paved roads. They are only recommended for off-road use on unpaved, low traction surfaces. The only time 4-wheel drive can be used on paved roads, is when the road surface is covered with snow or ice.