Just for the heck of it I decided to try the 15-40 amsoil instead of the Delo that's been run in the truck forever. I know this may sound lame but so far on this tank I'm averaging about 1. 5 mpg better than normal. Truck is a daily driver, same route to/from work every day so I pretty much can tell it's apples-to-apples comparison.
I'll be towing this weekend so I'll be anxious to see if it'll show a difference in my towing mpg.
I'll be towing this weekend so I'll be anxious to see if it'll show a difference in my towing mpg.