The average operating temperature of a passenger car/light truck engine is up to 235ºF, and higher under heavy loads. Motorists are becoming more familiar with the technologies responsible for this increased heat, specifically turbochargers and direct fuel injection. Automakers are designing engines using these performance-enhancing technologies to keep pace with increasingly strict fuel economy and emissions standards. Extreme heat, however, can lead to a host of problems, all of which reduce engine performance and life.
Deposits & Sludge
Heat can quickly break down motor oil, creating deposits on the intake valves, which impede airflow into the engine and contribute to poor sealing of the combustion chamber. This can lead to rough idle, misfire and reduced power and fuel economy.
Extreme heat depletes the additives sooner, altering the oil’s chemistry and preventing it from lubricating, cooling and protecting as designed. Sludge can form, which clogs narrow oil passages and prevents oil from reaching vital components, causing wear. Preventing sludge is particularly important in engines that use variable valve timing (VVT). Intricate parts sensitive to sludge can fail to operate properly, resulting in reduced performance.