NP242
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NP242 Selec Trac
Offered in XJ Cherokee, ZJ Grand Cherokee, WJ Grand Cherokee and KJ Liberty. Shift pattern: 2WD - 4 PARTTIME - 4 FULLTIME - N - 4 LO. It is an aluminum case with chain drive and can use a center differential for its front/rear power split or lock the shafts together depending on mode. Uses Dexron III ATF fluid.
It has a 2.72:1 low range and offers 2WD, 4WD Part-time, 4WD Full-time, Neutral & 4WD Low. The 2WD and 4WD Full Time options may be used on any road surface including dry pavement. The 4WD Part Time and 4WD Low may only be used on slick, low traction surfaces such as snow, sand, dirt, gravel and such. It is an "on the fly" transfer case allowing shifts between 2WD, Fulltime 4WD and Parttime 4WD at speed up to 55 MPH. 4WD Lo is handled differently, see below.
Selec-Trac Features:
- Either 2 or full-time 4-wheel drive in HI range;
- A N (Neutral) position to disengage the axles from the powertrain
- Part time four-wheel drive in Hi or Lo range.
Select either 2-wheel drive (2WD), full time 4-wheel drive (4 FULLTIME) or part time 4 wheel drive (4 PARTTIME) by moving the shift lever to desired mode. Mode selection can be made *WHILE THE VEHICLE IS MOVING AT ANY SPEED UP TO 55 MPH.*
NOTE: If shift lever is moved from one position to another
while the vehicle is not moving, it may be necessary to move
the vehicle forward or backwards slightly for the transfer case
to fully engage 4WD, especially in cold weather.
NOTE: it may be necessary when shifting on the fly between 2WD,
4 PARTTIME or 4 FULLTIME to briefly lift off the throttle once or
twice, especially in cold weather.
CAUTION: Never attempt to engage 4WD LO when vehicle is moving faster
than 2-3 mph (3-5 kmh). Transfer case damage may result.
*WARNING* you can't switch to 4WD LO "on the fly" like you can with
4WD HI.The vehicle must be moving slowly (2-3 mph) and the
*TRANSMISSION* must be shifted to neutral.
*WARNING: NEVER PARK YOUR VEHICLE WITH RANGE LEVER IN THE
N (NEUTRAL) POSITION. THE VEHICLE COULD ROLL UNEXPECTEDLY
EVEN IF AN AUTOMATIC TRANSMISSION IS PLACED IN PARK OR A
MANUAL TRANSMISSION IS IN GEAR.*
Modes
- 2WD or 4WD Full Time (2WD or 4 FULLTIME) - In either position, the vehicle may be operated on all road surfaces. In 4WD Full Time, Select Trac offers better traction when roads are wet, snow covered or icy. Use Selec-Trac 4WD Fulltime year-round (full time) if you wish. Comparable to what other vehicles call "all wheel drive."
- N Position (Neutral)- In this position the axles are disengaged from the powertrain. The vehicle may be towed without removing the propeller shafts. Place an automatic transmission in Park or a manual transmission in gear after the N position is engaged.
- 4WD Part Time High Position (4 PARTTIME) - This position provides 4WD for occasional use in low traction driving conditions such as snow, dirt etc. NOT FOR USE ON DRY PAVEMENT as transfer case damage may result.
- 4WD Lo Position (4 LO) - This position provides 4WD for occasional use when *OFF-ROAD* driving conditions require low speed pulling power. NOT FOR USE ON DRY PAVEMENT as transfer case damage may result.
WARNINGS / CAUTIONS
CAUTION: Never attempt to engage 4WD LO when vehicle is moving faster
than 2-3 mph (3-5 kmh). Transfer case damage may result.
*WARNING* you can't switch to 4WD LO "on the fly" like you can with
4WD HI. The vehicle must be moving slowly (2-3 mph) and the
*TRANSMISSION* must be shifted to neutral.
*WARNING: DO NOT DRIVE THE VEHICLE UNLESS THE TRANSFER CASE
IS FULLY ENGAGED. FAILURE TO COMPLETELY ENGAGE A POSITION
CAN CAUSE TRANSFER CASE DAMAGE OR LOSS OF POWER AND VEHICLE
CONTROL. BE SURE YOU KNOW THE SHIFT PATTERN OF YOUR VEHICLE.*
WARNING: DO NOT INSTALL SELECTIVE DRIVE HUBS ON SELEC-TRAC
VEHICLES. IF THESE HUBS ARE LEFT UNLOCKED WHEN THE VEHICLE
IS PARKED, THE VEHICLE COULD ROLL UNEXPECTEDLY--EVEN IF AN
AUTOMATIC TRANSMISSION IS IN PARK OR A MANUAL TRANSMISSION
IS IN GEAR.*
