We just got a new drum of mobil delvac mx15w40 the old drum is about 6 months old and has about 15 gallons left. The owner told me to get rid of the old drum.. so the 15 gallons are mine. I have a honda accord 2.2 4cyl 1997 mother has a 1998 honda accord v6 3.0 girlfriend has a toyota celica 1.8 2000 model. This would be free oil changes for me for awhile if i use it in these cars.. Is this oil ok to use in the summers in these small engines? will it hurt? just curious. ps. i can find very little on the delvac MX 15w40 from what i am reading it is better than regular delvac?