Isuzu D-MAX 2020 Owner's And Driver's Manual page 129

Protection of Engine Against Overcooling
Overcooling of the engine not only accelerates wear of the vital engine parts but also
deteriorates fuel economy.
The engine oil tends to harden with lowering temperatures. Use engine oil with a
viscosity suited to ambient temperature.
If you drive to a cold region in winter while using diesel fuel for warmer regions
that freezes at a relatively high temperature, the fuel may freeze. As the ambient
temperature decreases, the fuel in the fuel tank and pipes may freeze like slush,
making the engine hard to start.
NOTE
• The specifications of diesel fuel differ according to the season and region.
IMPORTANT INFORMATION
Engine Coolant
To prevent the engine damage due to
freezing of the engine coolant and to
protect the cooling system from corrosion,
mix the coolant and water to be an
appropriate concentration.
Engine Oil
Fuel
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