Lexus 2004 GX470 Owner's Manual page 565

CHASSIS
Chain installation
Install the chains on the rear tires as tightly as possible.
Do not use tire chains on the front tires. Retighten chains
after driving 0.5 — 1.0 km (1/4 — 1/2 mile).
When installing chains on your tires, carefully follow the
instructions of the chain manufacturer.
NOTICE
When jacking up or installing tire chains, be sure to turn
off the rear height control air suspension with the
"HEIGHT CONTROL OFF" switch and stop the engine.
Otherwise, the vehicle height may change because of
the automatic leveling function resulting in accident.
550
CAUTION
D Do not exceed 50 km/h (30 mph) or the chain
manufacturer's recommended
whichever is lower.
D Drive carefully avoiding bumps, holes, and sharp
turns, which may cause the vehicle to bounce.
D Avoid sharp turns or locked-wheel braking, as use of
chains may adversely affect vehicle handling.
D When driving with chains installed, be sure to drive
carefully. Slow down before entering curves to avoid
losing control of the vehicle. Otherwise an accident
may occur.
speed limit,