Bought car new in 2017. I've used the Ravenol SFE 5w-20 since new. I put about 20,000 highway miles per year on the car and change anywhere from 5,000 - 7500 miles. This is the first time I've gone to 10,000 miles. Car was tested at about 87K a few months ago and currently have 94K on it.
My...