2019 INFINITI QX80 brakes

10-24Technical and consumer information
cause serious personal injury or property
damage.
Hitch ball
Choose a hitch ball of the proper size and
weight rating for your trailer:
.The required hitch ball size is stamped on
most trailer couplers. Most hitch balls
also have the size printed on top of the
ball.
. Choose the proper class hitch ball based
on the trailer weight.
. The diameter of the threaded shank of
the hitch ball must be matched to the ball
mount hole diameter. The hitch ball
shank should be no more than 1/16”
smaller than the hole in the ball mount.
. The threaded shank of the hitch ball must
be long enough to be properly secured to
the ball mount. There should be at least 2
threads showing beyond the lock washer
and nut.
Ball mount
The hitch ball is attached to the ball mount
and the ball mount is inserted into the hitch
receiver. Choose a proper class ball mount
based on the trailer weight. Additionally, the
ball mount should be chosen to keep the
trailer tongue level with the ground.
Weight carrying hitches
A weight carrying or “dead weight” ball
mount is one that is designed to carry the
whole amount of tongue weight and gross
weight directly on the ball mount and on the
receiver.
Weight distribution hitch
This type of hitch is also called a “load-
leveling” or “equalizing” hitch. A set of bars
attach to the ball mount and to the trailer to
distribute the tongue weight (hitch weight)
of your trailer. Many vehicles cannot carry
the full tongue weight of a given trailer, and
need some of the tongue weight transferred
through the frame and pushing down on the
front wheels. This gives stability to the tow
vehicle.
A weight-distributing hitch system (Class IV)
is recommended if you plan to tow trailers
with a maximum weight over 5,000 lbs
(2,267 kg). Check with the trailer and towing
equipment manufacturers to determine if
they recommend the use of a weight-
distributing hitch system.
NOTE:
A weight-distributing hitch system may
affect the operation of trailer surge brakes.
If you are considering use of a weight-
distributing hitch system with a surge brake-equipped trailer, check with the
surge brake, hitch or trailer manufacturer
to determine if and how this can be done.
Follow the instructions provided by the
manufacturer for installing and using the
weight-distributing hitch system.
General set-up instructions are as follows:
1. Park unloaded vehicle on a level surface.
With the ignition switch in the ON
position and the doors closed, allow the
vehicle to stand for several minutes so
that it can level.
2. Measure the height of a reference point on the front and rear bumpers at the
center of the vehicle.
3. Attach the trailer to the vehicle and adjust the hitch equalizers so that the
front bumper height is within 0 - .5
inches (0 - 13 mm) of the reference
height measured in step 2. The rear
bumper should be no higher than the
reference height measured in step 2.
WARNING
Properly adjust the weight distributing
hitch so the rear of the bumper is no
higher than the measured reference
height when the trailer is attached. If
the rear bumper is higher than the

10-26Technical and consumer information
STI0745
Trailer lights
Your vehicle is equipped with a towing
package, which also includes the 7-pin trailer
harness connector located under the trailer
hitch cover on the rear bumper.
CAUTION
.When splicing into the vehicle elec-
trical system, a commercially avail-
able power-type module/converter
must be used to provide power for
all trailer lighting. This unit uses the
vehicle battery as a direct power
source for all trailer lights while using the vehicle tail light, stoplight and
turn signal circuits as a signal source.
The module/converter must draw no
more than 15 milliamps from the stop
and tail lamp circuits. Using a mod-
ule/converter that exceeds these
power requirements may damage
the vehicle’s electrical system. See a
reputable trailer retailer to obtain the
proper equipment and to have it
installed.
. Do not connect electrical devices that
draw more than 40 amps to the
vehicle. The fusible link may melt.
Trailer lights should comply with federal
and/or local regulations. For assistance in
hooking up trailer lights, contact an INFINITI
retailer or reputable trailer retailer.
Trailer brakes
When towing a trailer load of 3,500 lbs.
(1,587 kg) or more, trailers with a brake
system MUST be used. However, most
states require a separate braking system on
trailers with a loaded weight above a
specific amount. Make sure the trailer meets
the local regulations and the regulations
where you plan to tow.
Several types of braking systems are avail-
able. Surge Brakes -
The surge brake actuator is
mounted on the trailer tongue with a
hydraulic line running to each trailer wheel.
Surge brakes are activated by the trailer
pushing against the hitch ball when the tow
vehicle is braking. Hydraulic surge brakes are
common on rental trailers and some boat
trailers. In this type of system, there is no
hydraulic or electric connection for brake
operation between the tow vehicle and the
trailer.
Electric Trailer Brakes - Electric braking
systems are activated by an electronic signal
sent from a trailer brake controller (special
brake sensing module).
Have a professional supplier of towing
equipment make sure the trailer brakes are
properly installed and demonstrate proper
brake function testing.WARNING
Never connect a trailer brake system
directly to the vehicle brake system.
Pre-towing tips
. Be certain your vehicle maintains a level
position when a loaded or unloaded
trailer is hitched. Do not drive the vehicle
if it has an abnormal nose-up or nose-

10-28Technical and consumer information
4. Release the parking brake.
5. Drive slowly until the vehicle and trailerare clear from the blocks.
6. Apply and hold the brake pedal.
7. Have someone retrieve and store the blocks.
. While going downhill, the weight of the
trailer pushing on the tow vehicle may
decrease overall stability. Therefore, to
maintain adequate control, reduce your
speed and shift to a lower gear. Avoid
long or repeated use of the brakes when
descending a hill, as this reduces their
effectiveness and could cause overheat-
ing. Shifting to a lower gear instead
provides “engine braking” and reduces
the need to brake as frequently.
. If the engine coolant temperature rises to
a high temperature, see “If your vehicle
overheats” (P.6-14).
. Trailer towing requires more fuel than
normal circumstances.
. Avoid towing a trailer for your vehicle’s
first 500 miles (800 km).
. Have your vehicle serviced more often
than at intervals specified in the recom-
mended maintenance schedule shown in
the “9. Maintenance and schedules”
section. .
When making a turn, your trailer wheels
will be closer to the inside of the turn
than your vehicle wheels. To compensate
for this, make a larger than normal
turning radius during the turn.
. Crosswinds and rough roads will ad-
versely affect vehicle/trailer handling,
possibly causing vehicle sway. When
being passed by larger vehicles, be pre-
pared for possible changes in crosswinds
that could affect vehicle handling.
Do the following if the trailer begins to sway:
1. Take your foot off the accelerator pedal to allow the vehicle to coast and steer as
straight ahead as the road conditions
allow. This combination will help stabilize
the vehicle.
.Do not correct trailer sway by steering
or applying the brakes.
2. When the trailer sway stops, gently apply the brakes and pull to the side of
the road in a safe area.
3. Try to rearrange the trailer load so it is balanced as described earlier in this
section.
. Be careful when passing other vehicles.
Passing while towing a trailer requires
considerably more distance than normal
passing. Remember the length of the
trailer must also pass the other vehicle
before you can safely change lanes. .
Use the TOW mode or downshift the
transmission to a lower gear for engine
braking when driving down steep or long
hills. This will help slow the vehicle
without applying the brakes.
. Avoid holding the brake pedal down too
long or too frequently. This could cause
the brakes to overheat, resulting in
reduced braking efficiency.
. Increase your following distance to allow
for greater stopping distances while
towing a trailer. Anticipate stops and
brake gradually.
. INFINITI recommends that the cruise
control not be used while towing a
trailer.
. While towing a trailer, do not use the
following systems (if so equipped):
— the Lane Departure Warning (LDW) system
— the Lane Departure Prevention (LDP) system
— the Blind Spot Warning (BSW) system
— the Blind Spot Intervention
®(BSI)
system
— the Back-up Collision Intervention (BCI) system
— the Intelligent Cruise Control (ICC) system
— the Distance Control Assist (DCA) system

— the Forward Emergency Braking(FEB) with pedestrian detection sys-
tem
— the Predictive Forward Collision Warning (PFCW) system
. Some states or provinces have specific
regulations and speed limits for vehicles
that are towing trailers. Obey the local
speed limits.
. Check your hitch, trailer wiring harness
connections, and trailer wheel lug nuts
after 50 miles (80 km) of travel and at
every break.
. When launching a boat, do not allow the
water level to go over the exhaust tail
pipe or rear bumper.
. Make sure you disconnect the trailer
lights before backing the trailer into the
water or the trailer lights may burn out.
When towing a trailer, the transmission
fluid should be changed more frequently.
For additional information, see “9. Main-
tenance and schedules” section.
TOW mode
Using TOW mode is recommended when
pulling a heavy trailer or hauling a heavy
load. Push the TOW mode switch to activate
TOW mode. The TOW mode indicator light
in the meter illuminates when TOW mode is
selected. Push the TOW mode switch again to turn TOW mode off. TOW mode is
automatically cancelled when the ignition
switch is placed in the OFF position.
TOW mode includes the following features:
.
Grade logic — Adjusts transmission shifts
when pulling a trailer or hauling a load up
a grade.
. Downhill Speed Control (DSC) — auto-
matically downshifts when driving down
a grade with a trailer or heavy load to
help control vehicle speed.
Driving the vehicle in the TOW mode with no
trailer/load or light trailer/light load will not
cause any damage. However, fuel economy
may be reduced and the transmission/
engine driving characteristics may feel unu-
sual.
When towing a trailer, the transmission
fluid should be changed more frequently.
For additional information, see “9. Main-
tenance and schedules” section.
Trailer Sway Control
To minimize trailer sway, your vehicle may
apply braking to individual wheels based on
input from your vehicle sensors and vehicle
speed. Trailer Sway Control is a function of
the Vehicle Dynamic Control (VDC) system
and is active when the VDC function is
enabled.
CAUTION
If the VDC OFF switch is on (meaning
VDC system OFF), the Trailer Sway
Control is also disabled.
When Trailer Sway Control is in operation,
the VDC warning light blinks. When vehicle
control is regained, VDC warning light will
turn OFF.
For additional information about the VDC
system, see “Vehicle Dynamic Control (VDC)
system” (P.5-133).
If Trailer Sway Control activates:
1. Take your foot off the accelerator pedal to allow the vehicle to coast and steer as
straight ahead as the road conditions
allow. This combination will help stabilize
the vehicle.
CAUTION
Do not try to correct trailer sway by
steering or applying the brakes.
2. When the trailer sway stops, gently apply the brakes and pull to the side of
the road in a safe area.
Technical and consumer information10-29