Cold Starting and Oil Pumpability—Field Evaluations with Petroleum and Synthetic Engine Oils

A controlled cold starting and oil pumpability field test was conducted in Northern Ontario to quantify the expected advantages for 0W synthetic and part-synthetic multigrades over 5W30 mineral oils. In a second program the following winter, an attempt was made to establish the impact on starting performance of “real world” driving conditions.

In fact, four 4-cylinder vehicles could not distinguish between 0W and 5W multigrades differing in CCS viscosity by about 19 poise at −30°C. A full-synthetic oil did show a small pumpability advantage, but all the oils performed satisfactorily. Under real world driving conditions with two types of three year old vehicles, fuel dilution and fluctuations in battery output completely obscured oil viscosity effects from 0, 5 and 10W30 oils.