wheel torque JEEP COMMANDER 2006 1.G Owners Manual

TCS (Traction Control System)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system functions similar to
a limited slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in
either the “Partial Off” or “Full Off” modes. Refer to “ESP
(Electronic Stability Program)” in this section.
BAS (Brake Assist System)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
system detects an emergency braking situation by sens-
ing the rate and amount of brake application and then
applies optimum pressure to the brakes. This can help
reduce braking distances. The BAS complements the
anti-lock brake system (ABS). Applying the brakes very
quickly results in the best BAS assistance. To receive the
benefit of the system, you must apply continuous brak-
ing pressure during the stopping sequence. Do not
reduce brake pedal pressure unless braking is no longer
desired. Once the brake pedal is released, the BAS is
deactivated.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 133
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cause damage to the transmission. The torque converter
will refill within five seconds of shifting from Park into
any other gear position.
Rocking the Vehicle
If the vehicle becomes stuck in snow, sand, or mud, it can
often be moved by a rocking motion. Move the gear
selector rhythmically between D (Drive) and R (Reverse),
while applying slight pressure to the accelerator.
NOTE:The Electronic Stability Program (ESP) and
Traction Control (if equipped) should be turned OFF
before attempting to rock the vehicle. Refer to Section 3 of
this manual. (See page 131 for more information.)
The least amount of accelerator pedal pressure to main-
tain the rocking motion without spinning the wheels or
racing the engine is most effective. Racing the engine or
spinning the wheels, due to the frustration of not freeing
the vehicle, may lead to transmission overheating and
failure. Allow the engine to idle with the transmissionselector in N (Neutral) for at least one minute after every
five rocking-motion cycles. This will minimize overheat-
ing and reduce the risk of transmission failure during
prolonged efforts to free a stuck vehicle.
CAUTION!
When “rocking” a stuck vehicle by moving between
“First” and R (Reverse), do not spin the wheels faster
than 15 mph (24 km/h), or drivetrain damage may
result.
STARTING AND OPERATING 263
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FOUR-WHEEL DRIVE OPERATION
Quadra-Trac IOperating
Instructions/Precautions — If Equipped
The Quadra-Trac Iis a single speed (HI range only)
transfer case which provides convenient full-time
4–wheel drive. No driver interaction is required. This
transfer case divides engine torque almost evenly with 48
percent of engine torque to the front axle and 52 percent
of engine torque to the rear axle. The Brake Traction
Control System (BTC), which combines standard ABS
and Traction Control, provides resistance to any wheel
that is slipping to allow additional torque transfer to
wheels with traction.
NOTE:The Quadra-Trac Isystem is not appropriate
for conditions where LOW range is recommended. Refer
to “Off-Road Driving Tips” in this section.
Quadra-Trac IIOperating
Instructions/Precautions — If Equipped
The Quadra-Trac IItransfer case is fully automatic in the
normal driving 4 HI mode. The Quadra-Trac IItransfer
case provides three mode positions — four wheel drive
high range, neutral, and four wheel drive low range.
This transfer case is fully automatic in the 4 HI mode.
This transfer case divides engine torque almost evenly
with 48 percent of engine torque to the front axle and 52
percent of engine torque to the rear axle. When speed
differences are increased between the front and rear drive
shafts, the transfer case can transmit up to 100 percent of
available engine torque to the front or rear drive shafts.
When additional traction is required, the 4 LOW position
can be used to lock the front and rear driveshafts together
and force the front and rear wheels to rotate at the same
speed. The 4 LOW position is intended for loose, slippery
264 STARTING AND OPERATING

NOTE:If shift conditions/interlocks are not met, a
“CHECK SHIFT PROCEDURES” message will flash from
the EVIC (Electronic Vehicle Information Center). Refer
to “Electronic Vehicle Information Center (EVIC)” in
Section 4 of this manual. (See page 186 for more
information.)
Quadra-Drive IISystem — If Equipped
The optional Quadra-Drive IISystem features three
torque transfer couplings. The couplings include ELSD
(Electronic Limited Slip Differential) front and rear axles
and Quadra-Trac IItransfer case. The optional ELSD
axles are fully automatic and require no driver input to
operate. Under normal driving conditions the units func-
tion as standard axles balancing torque evenly between
left and right wheels. With a traction difference between
left and right wheels the coupling will sense a speed
difference. As one wheel begins to spin faster than the
other, torque will automatically transfer from the wheel
that has less traction to the wheel that has traction. Whilethe transfer case and axle couplings differ in design, their
operation is similar. Follow the Quadra-Trac IItransfer
case shifting information, preceding this section, for
shifting this system.
PARKING BRAKE
To set the parking brake, pull the lever up as firmly as
possible. When the parking brake is applied with the
ignition ON, the “Brake Warning Light” in the instru-
ment cluster will light.
STARTING AND OPERATING 269
5

Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4WD LOW range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
•After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
STARTING AND OPERATING 279
5

WARNING!
Raising the vehicle higher than necessary can make
the vehicle less stable. It could slip off the jack and
hurt someone near it. Raise the vehicle only enough
to remove the tire.
6. Remove the lug nuts and wheel.
7. Position the spare wheel/tire on the vehicle and install
the lug nuts with the cone-shaped end toward the wheel.
Lightly tighten the nuts. To avoid the risk of forcing the
vehicle off the jack, do not tighten the nuts fully until the
vehicle has been lowered.
8. Lower the vehicle by turning the jack screw counter
clockwise, and remove the jack and wheel blocks.9. Finish tightening the lug nuts. Push down on the
wrench while tightening for increased leverage. Alternate
nuts until each nut has been tightened twice. Correct
wheel nut tightness is 130 N·m (95 ft. lbs). If in doubt
about the correct tightness, have them checked with a
torque wrench by your authorized dealer or at a service
station.
10. Lower the jack to it’s fully closed position.
WARNING!
A loose tire or jack, thrown forward in a collision or
hard stop could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
11. Secure the tire, jack, and tools in their proper loca-
tions.
WHAT TO DO IN EMERGENCIES 337
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Inflation Pressures..................... 290
Jacking............................. 332
LifeofTires .......................... 294
Load Capacity.....................285,286
Pressure Monitor System (TPMS)........... 297
Pressure Warning Light.................. 181
Quality Grading....................... 417
Radial.............................. 293
Replacement......................... 295
Rotation............................. 304
Safety............................ 71,281
Sizes ............................... 282
Spare Tire........................... 333
Spinning ............................ 293
Tread Wear Indicators................... 294
Wheel Mounting....................... 337
Tongue Weight/Trailer Weight.............. 316
Torque Converter Clutch.................. 262
Tow Hooks, Emergency................... 340Tow/Haul Indicator Light................. 183
Towing ............................312,341
Disabled Vehicle....................... 341
Guide .............................. 315
Recreational.......................... 323
Weight .............................. 315
Traction Control......................... 133
Traction Control Light.................... 180
TrailerTowing .......................... 312
Cooling System Tips.................... 322
Hitches............................. 314
Minimum Requirements................. 317
Trailer and Tongue Weight................ 316
Wiring .............................. 320
TrailerTowingGuide ..................... 315
TrailerWeight .......................... 315
Transfer Case........................... 375
Maintenance.......................... 375
INDEX 435
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