JacobAziza -
IMO, your miles are "working miles". Your driving involves loading up your truck to move goods from A to B. Your MPG has a direct relationship to your job. Your truck is always doing "work". My miles are "commuting miles", which are indirectly related to my job. Essentially, I am "the goods" being transported from A to B and back again. It's not the same animal.
If you want to find out what your truck can do, you should do a weekend drive. Go see the Fresno Grizzlies,
!
CarloSW2