tire LEXUS RX400H 2008 User Guide

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2-4. Using other driving systems
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When driving
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CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the wet or slick road.
■Stopping distance when the ABS is operating will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you in the following situations.
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven roads
■Traction control may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the traction control system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.

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CAUTION
■When the slip indicator flashes and a warning buzzer sounds
This situation occurs immediately while VSC is activated. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS and VSC systems will not function correctly if different tires are fitted on
the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the
VDIM, and may cause the system to malfunction.

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2-5. Driving information
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When driving
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Off-road drivingYour vehicle is not designed to be driven off-road. However, in the event
that off-road driving cannot be avoided, please observe the following
precautions to help avoid the areas prohibited to vehicles.
● Drive your vehicle only in areas where off-road vehicles are permitted
to travel.
● Respect private property. Get owner’s permission before entering pri-
vate property.
● Do not enter areas that are closed. Honor gates, barriers and signs
that restrict travel.
● Stay on established roads. When conditions are wet, driving tech-
niques should be changed or travel delayed to prevent damage to
roads.
● Avoid driving on very steep, slippery roads and other surfaces, such as
sand, where the tires are liable to lose traction. Your vehicle may not
perform as well as conventional AWD on-road vehicles on these sur-
faces.
■Additional information for off-road driving
For owners in U.S. mainland, Hawaii and Puerto Rico:
To obtain additional information pertaining to driving your vehicle off-road, consult
the following organizations.
●State and Local Parks and Recreation Departments
●State Motor Vehicle Bureau
●Recreational Vehicle Clubs
●U.S. Forest Service and Bureau of Land Management

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When driving
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Vehicle load limits
■Total load capacity and seating capacity
These details are also described on the tire and loading information label.
(→ P. 3 4 0 )
CAUTION
■Overloading the vehicle
Do not overload the vehicle.
It may not only cause damage to the tires, but also degrade steering and braking
ability, resulting in an accident.
Vehicle load limits include total load capacity, seating capacity, towing
capacity and cargo capacity.
■Total load capacity: 925 lb. (420 kg)
Total load capacity means the combined weight of occupants, cargo and
luggage.
■Seating capacity: 5 occupants (Front 2, Rear 3)
Seating capacity means the maximum number of occupants whose esti-
mated average weight is 150 lb. (68 kg) per person.
Even if the number of occupants are within the seating capacity, do not
exceed the total load capacity.
■Towing capacity
Without towing package: 2000 lb. (907 kg)
With towing package: 3500 lb. (1588 kg)
Towing capacity means the maximum gross trailer weight (trailer weight
plus its cargo weight) that your vehicle is able to tow.
■Cargo capacity
Cargo capacity may increase or decrease depending on the weight and
the number of occupants.

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Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
● Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine/power control unit coolant
• Washer fluid
• Have a service technician inspect the level and specific gravity
of battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains match
the size of the tires.
●Tire pressure falls in winter as the outside temperature falls. Add
2.9 to 4.3 psi (20 to 30 kPa, 0.2 to 0.3 kgf/cm2 or bar) to the
standard tire inflation pressure.

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Selecting snow chainsUse the correct snow chain size when mounting the snow chains. Chain
size is regulated for each tire sizes.
Side chain 0.12 in. (3 mm) in diameter
1.18 in. (30 mm) in length
0.39 in. (10 mm) in width
Cross chain 0.16 in. (4 mm) in diameter
0.98 in. (25 mm) in length
0.55 in. (14 mm) in width
Regulations on the use of snow chains
● Regulations regarding the use of tire chains vary according to location
and type of road. Always check local regulations before installing
chains.
● Install the chains on the front tires.
● Retighten the chains after driving 1 /4 - 1 /2 mile (0.5 - 1.0 km).

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When driving
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■Snow chain installation
Observe the following precautions when installing and removing chains.
●Install and remove tire chains in a safe location.
●Install tire chains on the front tires only. Do not install tire chains on rear tires.
●Install tire chains following the instructions provided in the accompanying instruc-
tions.
CAUTION
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or serious
injury.
●Use tires of the size specified for your vehicle.
●Maintain the recommended level of air pressure.
●Do not drive in excess of 75 mph (120 km/h), regardless of the type of snow tires
being used.
●Use snow tires on all, not just some wheels.
■Driving with snow chains
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being used,
or 30 mph (50 km/h), whichever is lower.
●Avoid driving on bumpy road surfaces or over potholes.
●Avoid sudden turns and braking, as use of chains may adversely affect vehicle
handling.
●Slow down sufficiently before entering a curve to ensure that vehicle control is
maintained.

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NOTICE
■Repairing or replacing snow tires
Request repairs of and obtain replacement snow tires from Lexus dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the operation of
the tire air pressure sensor.
■Fitting tire chains
The tire air pressure sensor may not function correctly when tire chains are fitted.

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Connecting trailer lightsWith tow hitch receiver
Use the socket located under the rear bumper.
Without tow hitch receiver
Use the wire harness stored in the rear end under body.
■Front Emblem
■Before towing
Check that the following conditions are met:
●The vehicle's tires are properly inflated. ( →P. 3 4 0 )
●Trailer tires are inflated according to the trailer manufacturer's recommendation.
●All trailer lights work
●All lights work each time you connect them.
●The trailer ball is set up at the proper height for the coupler on the trailer.
●The vehicle remains level when a loaded or unloaded trailer is hitched. Do not
drive if the vehicle is not level, and check for improper tongue load, overloading,
worn suspension, or other possible causes.
●The trailer cargo is securely loaded.
●The rear view mirrors conform to all applicable federal, state/provincial or local
regulations. If they do not, install rear view mirrors appropriate for towing pur-
poses.
With towing package
Without towing package
On vehicles with a towing package, the
front emblem has openings, which are
designed to improve the cooling perfor-
mance.

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CAUTION
■Hitches
●If you wish to install a trailer hitch, contact your Lexus dealer.
●Use only a hitch that conforms to the total trailer weight requirement.
●Follow the directions supplied by the hitch manufacturer.
●Lubricate the hitch ball with a light coat of grease.
●Remove the trailer hitch whenever you are not towing a trailer. After removing
the hitch, seal any mounting hole in the vehicle body to prevent entry of any sub-
stances into the vehicle.
■When towing a trailer
●If the total trailer weight exceeds 1000 lb. (450 kg), trailer brakes are required.
●Never tap into your vehicle's hydraulic system, as this will lower the vehicle's
braking effectiveness.
●Never tow a trailer without using a safety chain securely attached to both the
trailer and the vehicle. If damage occurs to the coupling unit or hitch ball, there is
danger of the trailer wandering into another lane.
NOTICE
■When installing a trailer hitch
●Use only the position recommended by your Lexus dealer. Do not install the
trailer hitch on the bumper; this may cause body damage.
●Do not use axle-mounted hitches, as they can cause damage to the axle housing,
wheel bearings, wheels or tires.
■Brakes
Lexus recommends trailers with brakes that conform to all applicable federal and
state/provincial regulations.