10-24-2011, 10:11 PM
Join Date: May 2010
Location: Nova Scotia
From the Owner Manual for a 2004 Wrangler with "Command Trac" or "Rock Trac" if so equipped. This Owner Manual is available online at jeep.com.
The transfer case provides four mode positions — two (rear) wheel drive high range, four wheel drive high range, neutral, and four wheel drive low range.
This transfer case is intended to be driven in the two wheel drive (2H) position for normal street and highway conditions such as dry hard surfaced roads.
In the events when additional traction is required, the transfer case 4H and 4L positions can be used to lock the front and rear driveshafts together and force the front and rear wheels to rotate at the same speed. This is accomplished by simply moving the shift lever to these positions. The 4H and 4L positions are intended for loose, slippery road surfaces only. Driving in the 4H and 4L positions on dry hard surfaced roads may cause increased tire wear and damage to the driveline components.
The 4WD indicator light, located in the instrument panel, alerts the driver that the vehicle is in four wheel drive and that the front and rear driveshafts are locked together.
This light illuminates when the transfer case is shifted to either the 4H or 4L positions.
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NOTE: Do not attempt to make a shift while only the front or rear wheels are spinning. The transfer case is not equipped with a synchronizer and therefore the front and
rear driveshafts speeds must be equal for the shift to take place. Shifting while only the front or rear wheels are spinning can cause damage to the transfer case.
When operating your vehicle in 4L, the engine speed is approximately three times that of the 2H or 4H positions at a given road speed. Take care not to overspeed the engine and do not exceed 25 mph (40 km/h).
Proper operation of four wheel drive vehicles depends on tires of equal size, type, and circumference on each wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction, there is a tendency to exceed safe turning and stopping speeds. Do not go faster than road conditions permit.
You or others could be injured if you leave the vehicle unattended with the transfer case in the N (Neutral) position without first fully engaging the parking brake. The transfer case N (Neutral) position disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move regardless of the transmission position. The parking brake should always be applied when the driver is not in the vehicle.
For additional information on the appropriate use of each transfer case mode position, see the information below:
Rear Wheel Drive High Range — Normal street and
highway driving. Dry hard surfaced roads.
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Four Wheel Drive High Range—Locks the front and rear driveshafts together. Forces the front and rear wheels to rotate at the same speed. Additional traction for loose, slippery road surfaces.
N (Neutral) Position
Neutral—Disengages both the front and rear driveshafts from the powertrain. To be used for flat towing behind another vehicle. Refer to “Recreational Towing” in Section
5 of this manual.
Four Wheel Drive Low Range—Locks the front and rear driveshafts together. Forces the front and rear wheels to rotate at the same speed. Additional traction and maximum
pulling power for loose, slippery road surfaces only. Do not exceed 25 mph (40 km/h).
2H to 4H or 4H to 2H
Shifting between 2H and 4H can be made with the vehicle stopped or in motion. If the vehicle is in motion, shifts can be made up to 55 mph (88 km/h). With the vehicle in motion, the transfer case will engage/disengage faster if you momentarily release the accelerator pedal after completing the shift. Apply a constant force when shifting the transfer case lever.
4H to 4L or 4L to 4H
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift an automatic transmission to N (Neutral) or depress the clutch pedal on a manual transmission. While the vehicle is coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer case lever firmly to the desired position. Do not pause in transfer case N (Neutral).
NOTE: Pausing in transfer case N (Neutral) in vehicles equipped with an automatic transmission may require shutting the engine OFF to avoid gear clash while completing the shift. If difficulty occurs, shift the automatic transmission to N (Neutral), hold foot on brake, and turn the engine OFF. Make shift to desired mode.
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NOTE: Shifting into or out of 4L is possible with the vehicle completely stopped, however, difficulty may occur due to the mating teeth not being properly aligned.
Several attempts may be required for clutch teeth alignment and shift completion to occur. The preferred method is with the vehicle rolling at 2 to 3 mph (3 to 5
km/h). Avoid attempting to engage or disengage 4L with the vehicle moving faster than 2 to 3 mph (3 to 5 km/h).
2003 Jeep TJ Sport - 4.0L - 275,000 kms