flat tire LEXUS RX450h 2018 Service Manual

6858-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL _U_OM48F85URemove the center wheel ornament by pushing from the reverse side.
Be careful not to lose the wheel ornament.
Stand the tire against the bumper
with the inner surface facing toward
you. Pass the hoist assembly and
holding bracket through the
wheel opening.
Fully depress the secondary latch
and install the bracket to the
hoist assembly . WARNING ■
Stowing the flat tire
Failure to follow steps listed under stow ing the tire may re sult in damage to
the spare tire carrier and loss of the ti re, which could result in serious injuryor death.
Stowing the flat tire, jack and all tools (RX450hL) 1
2
C
B
3
A B
C

6878-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL _U_OM48F85U■
The compact spare tire ●
The compact spare tire is identified by the label “TEMPORARY USE ONLY” on the
tire sidewall.
Use the compact spare tire tempor arily, and only in an emergency.●
Make sure to check the tire inflation pressure of the compact spare tire. ( → P. 717)■
When using the compact spare tire
As the compact spare tire is not equipped wi th a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare tire will not be indicated by the tire pressure
warning system. Also, if you replace the compac t spare tire after the tire pressure warn-
ing light comes on, the light remains on. ■
When the compact spare tire is equipped
When driving with the compact spare tire inst alled, the vehicle height will be different
than when driving with standard tires. ■
If you have a flat front tire on a road covered with snow or ice
Install the compact spare tire on one of the re ar wheels of the vehicle. Perform the follow-
ing steps and fit tire chains to the front tires:
Replace a rear tire with the compact spare tire.
Replace the flat front tire with the tire removed from the rear of the vehicle.
Fit tire chains to the front tires. 1
2
3

6898-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL _U_OM48F85UNOTICE ■
Be careful when driving over bumps with th e compact spare tire installed on the vehi-
cle
When driving with the compact spare tire installed, the vehi cle height will be different
than when driving with standard tires. Be careful when driving over uneven road sur-
faces, etc. ■
Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire.
Tire chains may damage the vehicle body and adversely affect driving performance.■
When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and trans-
mitter, contact your Lexus dealer as the tire pressure warning valve and transmitter
may be damaged if not handled correctly. ■
When stowing the flat tire (RX450hL) ●
Ensure that there is no object caught between the tire and the vehicle underbody. ●
Securely tighten the spare tire clamp bolt to hold the spare wheel carrier by the hook. ●
Stow the flat tire in the spare tire location. Failure to do so may cause damage to the
spare tire carrier. Pr oper storage reduces the possibilit y of injury in a collision or
during sudden braking. ●
Have the flat tire repaired and the spare tire replaced with it as soon as possible. ■
Proper storage of the spare tire (RX450hL)
●
If the spare tire clamp bolt is turned withou t a tire on the hoist assembly, the wire cable
may not be able to be lowered. If the wire cable cannot be lowered, contact your
Lexus dealer. ●
If the hoist assembly is slanted when stowing a
tire, the hoist assembly may become stuck in
the wheel opening and the tire may not be
raised properly, causing damage to the wheel
or the wire cable.

7179-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85U 
Type ASteering Free play Less than 1.2 in. (30 mm)
Tires and wheels Tire size 235/65R18 106V, T165/90D18 107M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure) Front tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Rear tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Spare tire
60 psi (420 kPa, 4.2 kgf/cm 2
or bar)
Driving at high speeds (above 100 mph [160 km/h])
(in countries where such speeds are permitted by
law)
Add 5 psi (30 kPa, 0.3 kgf/cm 2
or bar) to the
front and rear tires. Never exceed the maximum
cold tire inflation pressu re indicated on the tire
sidewall.
Wheel size 18 × 8 J, 18 × 4 T (spare)
Wheel nut torque 76 ft•lbf (103 N•m, 10.5 kgf•m)

718 9-1. Specifications
RX450h_RX450hL _U_OM48F85U 
Type B Tire size 235/55R20 102V, T165/90D18 107M (spare)
Tire inflation pressure
(Recommended cold tire
inflation pressure) RX450h:
Front tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Rear tire
33 psi (230 kPa, 2.3 kgf/cm 2
or bar)
Spare tire
60 psi (420 kPa, 4.2 kgf/cm 2
or bar)
Driving at high speeds (above 100 mph [160 km/h])
(in countries where such speeds are permitted by
law)
Add 11 psi (70 kPa, 0.7 kgf/cm 2
or bar) to the
front and rear tires. Never exceed the maximum
cold tire inflation pressu re indicated on the tire
sidewall.
RX450hL:
Front tire
35 psi (240 kPa, 2.4 kgf/cm 2
or bar)
Rear tire
35 psi (240 kPa, 2.4 kgf/cm 2
or bar)
Spare tire
60 psi (420 kPa, 4.2 kgf/cm 2
or bar)
Driving at high speeds (above 100 mph [160 km/h])
(in countries where such speeds are permitted by
law)
Add 9 psi (62 kPa, 0.6 kgf/cm 2
or bar) to the
front and rear tires. Never exceed the maximum
cold tire inflation pressu re indicated on the tire
sidewall.
Wheel size 20 × 8 J, 18 × 4 T (spare)
Wheel nut torque 76 ft•lbf (103 N•m, 10.5 kgf•m)

724 9-1. Specifications
RX450h_RX450hL _U_OM48F85UTire size ( → P. 726)
DOT and Tire Identification Number (TIN) ( → P. 725)
Location of treadwear indicators ( → P. 611)
Tire ply composition and materials Plies are layers of rubber-c oated parallel cords. Cords are the strands which form the
plies in a tire.
Radial tires or bias-ply tires A radial tire has “RADIAL” on the sidewall. A tire not marked “RADIAL” is a bias-ply
tire.
TUBELESS or TUBE TYPE A tubeless tire does not have a tube and air is directly put into the tire. A tube type tire
has a tube inside the tire and the tube maintains the air pressure.
Load limit at maximum cold tire inflation pressure ( → P. 615)
Maximum cold tire inflation pressure ( → P. 717)This means the pressure to which a tire may be inflated.
Uniform tire quality grading For details, see “Uniform Tire Quality Grading” that follows.
Summer tires or all season tires ( → P. 615)An all season tire has “M+S” on the side wall. A tire not marked “M+S” is a summer
tire.
“TEMPORARY USE ONLY” A compact spare tire is identified by the phrase “TEMPORARY USE ONLY” molded
on its sidewall. This tire is design ed for temporary emergency use only.1
2
3
4
5
6
7
8
9
10
11

7299-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85U■
Temperature A, B, C
The temperature grades are A (the highes t), B, and C, representing the tire’s
resistance to the generation of heat and its ability to dissipate heat when
tested under controlled conditions on a specified indoor laboratory test
wheel. Sustained high temperature can cause the ma terial of the tire to degenerate and
reduce tire life, and excessive temperature can lead to sudden tire failure.
Grade C corresponds to a level of perfor mance which all passenger car tires must
meet under the Federa l Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance on the laboratory test
wheel than the minimum required by law.
Warning: The temperature grades of a tire assume that it is properly inflated and
not overloaded.
Excessive speed, underi nflation, or excessive loading, either separately or in com-
bination, can cause heat buildup and possible tire failure.

730 9-1. Specifications
RX450h_RX450hL _U_OM48F85UGlossary of tire terminology Tire related term Meaning
Cold tire inflation pressure Tire pressure when the vehicle has been parked for
three hours or more, or has no t been driven more than 1
mile or 1.5 km un der that condition
Maximum inflation pres-
sure The maximum cold inflated pr essure to which a tire may
be inflated, shown on the sidewall of the tire
Recommended inflation
pressure Cold tire inflation pressure recommended by a manu-
facturer
Accessory weight The combined weight (in exce ss of those standard items
which may be replaced) of hybrid transmission, power
steering, power brakes, power windows, power seats,
radio and heater, to the extent that these items are avail-
able as factory-installed eq uipment (whether installed
or not)
Curb weight The weight of a motor vehicle with standard equipment,
including the maximum capacity of fuel, oil and coolant,
and if so equipped, air co nditioning and additional
weight optional engine
Maximum loaded vehicle
weight The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight 150 lb. (68 kg) times the numb er of occupants specified
in the second column of Table 1
* that follows
Occupant distribution Distribution of occupants in a vehicle as specified in the
third column of Table 1
* below

7319-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85UProduction options weight The combined weight of in stalled regular production
options weighing over 5 lb. (2.3 kg) in excess of the
standard items which they re place, not previously con-
sidered in curb weight or accessory weight, including
heavy duty brakes, ride leve lers, roof rack, heavy duty
12-volt battery, and special trim
Rim A metal support for a tire or a tire and tube assembly
upon which the tire beads are seated
Rim diameter
(Wheel diameter) Nominal diameter of the bead seat
Rim size designation Rim diameter and width
Rim type designation The industry manufacturer’s designation for a rim by
style or code
Rim width Nominal distance between rim flanges
Vehicle capacity weight
(Total load capacity) The rated cargo and luggage load plus 150 lb. (68 kg)
times the vehicle’s desi gnated seating capacity
Vehicle maximum load on
the tire The load on an individual tire that is determined by dis-
tributing to each axle its share of the maximum loaded
vehicle weight, and dividing by two
Vehicle normal load on the
tire The load on an individual tire that is determined by dis-
tributing to each axle its sh are of curb weight, accessory
weight, and normal occupant weight (distributed in
accordance with Table 1
* below), and dividing by two
Weather side The surface area of the rim not covered by the inflated
tire
Bead The part of the tire that is made of steel wires, wrapped
or reinforced by ply cords an d that is shaped to fit the
rimTire related term Meaning

732 9-1. Specifications
RX450h_RX450hL _U_OM48F85UBead separation A breakdown of the bond between components in the
bead
Bias ply tire A pneumatic tire in which the ply cords that extend to
the beads are laid at altern ate angles substantially less
than 90 degrees to the centerline of the tread
Carcass The tire structure, except tread and sidewall rubber
which, when inflated, bears the load
Chunking The breaking away of pieces of the tread or sidewall
Cord The strands forming th e plies in the tire
Cord separation The parting of cords from adjacent rubber compounds
Cracking Any parting within the tread, sidewall, or innerliner of
the tire extending to cord material
CT A pneumatic tire with an inverted flange tire and rim
system in which the rim is designed with rim flanges
pointed radially inward and the tire is designed to fit on
the underside of the rim in a manner that encloses the
rim flanges inside the air cavity of the tire
Extra load tire A tire designed to operate at higher loads and at higher
inflation pressures than the corresponding standard tire
Groove The space between two adjacent tread ribs
Innerliner The layer(s) forming the insi de surface of a tubeless tire
that contains the inflating medium within the tire
Innerliner separation The parting of the innerliner from cord material in the
carcassTire related term Meaning