Page 17 - Jeep Jamboree Ultimate Guide To Safe Common Sense Off-Roading
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4-WHEEL DRIVE
Not all four-wheel drive systems function the same way, so it’s important to understand the differences
so you can better use your vehicle and limit your chances of getting stuck.
TRACTION CONTROL PART-TIME 4WD
Many newer vehicles come equipped with some Part-time 4WD, or on-demand 4WD, is a system
version of traction control. Traction control will that allows 4WD to be called upon when needed.
keep the vehicle moving forward by alerting the When 4WD is not engaged, the vehicle acts like
computer to brake as necessary in order to keep a 2WD vehicle, with the rear wheels receiving
the wheels from spinning and losing traction. It all of the torque. Operating in 2WD provides
may have a simple on/off switch or come with significantly better fuel economy on the highway.
multiple settings. Refer to your owner’s manual to Part-time 4WD vehicles should only be driven
learn more about its capabilities. in 2WD on-road to avoid transmission wind-up.
When engaged in 4WD, part-time systems will
ALL-WHEEL DRIVE not allow the front and rear axles to operate at
Like vehicles with full-time 4WD, AWD vehicles different speeds because there’s not a differential
utilize a center differential to deliver power to all in the transfer case. A part-time 4WD vehicle can
four wheels. But most AWD vehicles don’t have a operate in 2WD, 4WD High and 4WD Low.
transfer case that splits and locks the power 50/50
front to back, so they will operate like front-wheel FULL-TIME 4WD
drive vehicles most of the time – only delivering Full-time 4WD, or permanent 4WD, is a system that
torque to the rear wheels as needed. Automatic powers all four wheels at all times. A differential
sensors determine when a wheel is losing traction in the transfer case makes it possible to be in
and applies torque to the wheels that have constant 4WD on all surfaces. This differential
traction. AWD is primarily used on-road. It may prevents transmission wind-up by enabling the
help in some light off-road situations, but should front and rear driveshafts to rotate at different
not be confused with a truly 4WD-capable vehicle. speeds. When you turn, this allows the inside tire
to slow down and the outside tire to speed up.
2WD HIGH Many full-time rigs have a center differential lock,
Used for normal highway which may be controlled by an electronic traction
driving. Torque is only
provided to the front or rear control system or a manual lock. A full-time 4WD
wheels, resulting in better fuel vehicle can operate in 4WD High and 4WD Low
economy.
ENGAGING FOUR-WHEEL DRIVE
4WD HIGH Activating 4WD is done by the transfer case,
Used on dirt roads and easier which transfers power from the driveshaft to the
trails that require steady
momentum. Reduces the front and rear axles. You may need to come to a
likelihood of slipping and complete stop and put your vehicle in neutral or
spinning wheels on surfaces like
snowy roads and muddy dirt. park before manually shifting into 4WD with a
gear stick or lever. In some vehicles, 4WD can be
engaged with just the push of a button. Check
4WD LOW
Provides more torque, not your owner’s manual to ensure that that you know
traction. 4WD Low is used to how to properly use your 4WD system.
negotiate difficult terrain when
slower speeds and greater
torque are required.
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