Toyota COASTER Owner's Manual page 468

Oil viscosity (10W-30 is explained here as an example):
• The 10W in 10W-30 indicates the characteristic of the oil which
allows cold startability. Oils with a lower value before the W allow
for easier starting of the engine in cold weather.
• The 30 in 10W-30 indicates the viscosity characteristic of the oil
when the oil is at high temperature. An oil with a higher viscosity
(one with a higher value) may be better suited if the vehicle is
operated at high speeds, or under extreme load conditions.
*
: Saudi Arabia, Sultanate of Oman, Bahrain, United Arab Emirates, Qatar
and Kuwait
COASTER_GW-E
COASTER_OM_General_OM36742W
9-1. Specifications
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