Cold-Temperature Performance is not Just Reserved for Sub-Zero Conditions

Cold-Temperature Performance is not Just Reserved for Sub-Zero Conditions

Startup lubrication is directly affected by a lubricant’s cold-flow ability, and the impact is felt at higher temperatures than most consumers realize. An oil’s cold-temperature performance refers to its ability to flow when the engine is cold, or below typical operating temperature (212°F), and not simply to what feels cold to humans – even some summer days can be cold to an engine.

Pour point has been defined as the lowest temperature at which a motor oil will continue to flow under prescribed conditions. ASTM D97 spells out the standardized procedure for determining
an oil’s pour point. After heating it to 45°C (113°F) the sample is slowly cooled and tilted sideways every time the temperature drops 3°C (5°F). When the oil stops flowing it has reached the pour point.

AMSOIL synthetic motor oils have lower pour points and better cold-cranking capabilities than petroleum-based products. Long after petroleum oils have solidified, AMSOIL synthetic motor oils continue to flow.

The problems with cold weather go beyond this, however. Motor oils really need to be heated well above the pour point to achieve the desired pumping viscosity. Even at just below freezing (32°F), motor oil can become difficult to pump into the engine. It sits in the pan while the friction from
moving parts heats the engine and conducts this heat down into the pan. As you can imagine, this lack of oil in an engine with fast moving parts has consequences. Cold-weather start-ups are a leading cause of engine wear.