Page 589 of 660
5899-1. Specifications
9
Vehicle specifications
IS350 AWD/IS350/IS300 AWD/IS300_U
Engine
IS350 AWD/IS350/IS300 AWDIS300
Model3.5 L 6-cylinder (2GR-FKS)
engine2.0 L 4-cylinder (8AR-FTS)
engine
Type 6-cylinder V type,
4-cycle, gasoline 4-cylinder in line,
4-cycle, gasoline
(with turbocharger)
Bore and stroke
3.70
3.27 in.
(94.0 83.0 mm) 3.39
3.39 in.
(86.0 86.0 mm)
Displacement 210.9 cu. in. (3456 cm3) 121.9 cu. in. (1998 cm3)
Valve clearance
(engine cold)Automatic adjustment
Drive belt tensionAutomatic adjustment
Fuel
Fuel typeUnleaded gasoline only
Octane Rating91 (Research Octane Number 96) or higher
Fuel tank capacity
(Reference)17.5 gal. (66.3 L, 14.6 Imp. gal.)
Page 598 of 660

5989-1. Specifications
IS350 AWD/IS350/IS300 AWD/IS300_U
■Gasoline quality
In very few cases, driveabilit y problems may be caused by th e brand of gasoline you are
using. If driveability problems persist, try ch anging the brand of gasoline. If this does not
correct the problem, consult your Lexus dealer.
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to avoid the
build-up of engine deposits.
●All gasoline sold in the U.S.A. contains minimum detergent additives to clean and/or
keep clean intake systems, per EPA’s lowest additives concentration program.
●Lexus strongly recommends the use of Top Tier Detergent Gasoline. For more informa-
tion on Top Tier Detergent Gasoline and a lis t of marketers, please go to the official
website www.toptiergas.com.
■Recommendation of the use of low emission gasoline
Gasolines containing oxygenates such as et hers and ethanol, as well as reformulated
gasolines, are available in some cities. Thes e fuels are typically acceptable for use, pro-
viding they meet other fuel requirements.
Lexus recommends these fuels, since the form ulations allow for reduced vehicle emis-
sions.
Fuel information
You must only use unleaded gasoline.
Select premium unleaded gasoline with an octane rating of 91 (Research
Octane Number 96) or higher requir ed for optimum engine performance
and fuel economy.
If the octane rating is less than 91, damage to the engine may occur and may
void the vehicle warranty.
At minimum, the gasoline you use should meet the specifications of ASTM
D4814 in the U.S.A..
Page 599 of 660

5999-1. Specifications
9
Vehicle specifications
IS350 AWD/IS350/IS300 AWD/IS300_U
■Non-recommendation of the use of blended gasoline
●If you use gasohol in your vehicle, be sure that it has an octane rating no lower than 91.
●Lexus does not recommend the use of gasoline containing methanol.
■Non-recommendation of the use of gasoline containing MMT
Some gasoline contains an octane enhancing additive called MMT (Methylcyclopenta-
dienyl Manganese Tricarbonyl).
Lexus does not recommend the use of gasoline that contains MMT. If fuel containing
MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the instru ment cluster may come on. If this happens,
contact your Lexus dealer for service.
■If your engine knocks
●Consult your Lexus dealer.
●You may occasionally notice light knocking for a short time while accelerating or driv-
ing uphill. This is normal and there is no need for concern.
●Use only gasoline containing up to 15% etha-
nol.
DO NOT use any flex-fuel or gasoline that
could contain more than 15% ethanol, includ-
ing from any pump labeled E30, E50, E85
(which are only some examples of fuel con-
taining more than 15% ethanol).DO NOT use gasoline con-
taining more than 15% ethanol.
(30% ethanol)
(50% ethanol)
(85% ethanol)
Page 600 of 660

6009-1. Specifications
IS350 AWD/IS350/IS300 AWD/IS300_U
NOTICE
■Notice on fuel quality
●Do not use improper fuels. If improper fuels are used, the engine will be damaged.
●Do not use leaded gasoline.
Leaded gasoline can cause damage to your vehicle’s three-way catalytic converters
causing the emission control system to malfunction.
●Do not use gasohol other than the type previously stated.
Other gasohol may cause fuel system damage or vehicle performance problems.
●Using unleaded gasoline with an octane numb er or rating lower than the level previ-
ously stated may cause pe rsistent heavy knocking.
At worst, this may lead to engine da mage and will void the vehicle warranty.
■Fuel-related poor driveability
If poor driveability (poor hot starting, vaporization, engine knocking, etc.) is encoun-
tered after using a different type of fuel, discontinue the use of that type of fuel.
■When refueling with gasohol
Take care not to spill gasohol. It can damage your vehicle’s paint.