Lexus GS300 1998 Owner's Manual page 408

63G001
" 1
New tread 2 Tread wear indicator
3 Worn tread
Replace the tires when the tread wear indicators show.
The location of the tread wear indicators is shown by the
∆
"TWI" or " " marks molded on the sidewall of each tire.
The tires on your Lexus have built–in tread wear indicators to
help you know when the tires need replacement. When the
tread depth wears to 1.6 mm (0.06 in.) or less, the indicators
will appear. If you can see the indicators in two or more
adjacent grooves, the tire should be replaced.
CHASSIS
395