Winter Weight (0W40) Engine Oil – BMW and MINI

This answer is applicable for many BMWs in addition to the one listed below.

Q
I hear people at work talking about using a lighter weight motor oil in the winter. Where I live, it’s below freezing (sometimes below zero) every night from December till March. I use 15W-40 year round. Should I lose some weight?
Fritz

A
Lighter weight, synthetic motor oils, such as Lubro Moly 0W-40, get distributed throughout the engine much faster than the heavier mineral oil you’re using. Here in New Hampshire it gets pretty cold, too. (We like to describe it as 9 months of winter and 3 months of bad skiing.) We change our oil every 6 months. In the winter we typically use the Lubro-Moly 0W-40 in our BMWs. For the summer, we change back to 5W-30, 5W-40 or 10W-40 (depending on the model and the age of the vehicle). We highly recommend this routine for longer engine life.

Motor Oils: