In most cases you are wrong and she is right, unless the operator has zero interest in operating smart to make it work. Let's say the truck gets 8mpg overall, including idling time, and fuel is $3 per gallon. That's .375cpm fuel cost. When fuel is at $3 per gallon the fsc is pretty good. Let's say it averages 20cpm overall although I believe it will be higher overall but we'll use 20cpm. Let's say the truck gets $1.20 a mile. The split (60/40) is .72/.48cpm so the driver has a choice of .92cpm-.375cpm=.545cpm buying fuel or .48cpm not buying fuel.
At $3 for fuel I see the average fsc being at least 25cpm so it's probably more like .975-.375=.60 or .48cpm. The side buying fuel is going to be 10-12cpm ahead of the side not buying fuel. Some of that will get used up on deadhead but an operator that learns the zones and the business and runs smart can make a few extra cents for every mile they run by buying the fuel and taking the 60% side.
Why am I not taking the 60% side? Because if the driver has to buy the fuel he's not going to offer to fill some guys truck on my card for $100 bucks cash. Idiots with somebody else's fuel card do it all the time. He's also hopefully going to run a little smarter since he's got an investment in the operation, even if it's only his fuel money. If it's nothing but hold the wheel and aim the truck he has zero incentive to run smart and economically.
Leo Bricker, 73's K5LDB, OOIDA 677319
Owner, Panther trucks 5507, 5508, 5509
Highway Watch Participant, Truckerbuddy
EO Forum Moderator
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