Let me show you people some math for "my" situation and "my" diesel. "Your" math may be different if you live in Canada or England or where ever.
I traveled 5,000 miles on vacation this year. Unlike some of you on here I keep records of every fuel stop because I need to keep tract of costs.
My truck averaged 11.0 MPG on my trip. Sooooo 5,000 divided by 11 = 455 gallons of diesel for my vacation. :E
I don't have my spreadsheet in front of me so I will go with the cheapest price right now of where "I" live. It's $4.00 a gallon for diesel right now. Regular gas is $3.90 a gallon where "I" live at the same station.
Soooo, $4.00 x 455= $1,820 dollars in fuel for my vacation.
Soooo, if I owned a gas truck the figures would be something like this. Where "I" live gas is $3.90 a gallon. Physics say if I had a gas truck it would get right at 8 MPG pulling "my" trailer. (yes, yes, yes I know some of you are going to say, but, but, but my gas truck gets 15 MPG towing my 15K trailer. Cool story bro) :B
5000 divided by 8 = 625 gallons of gas for my vacation. So, $3.90 x 625 gallons of gas = $2,437 dollars.
Bottom line: "My" vacation this year cost me $1,820 in diesel. If I would have towed with a gas truck it would have cost me $2,437.
So on this ONE vacation trip for this year I saved $600. :C
BTW I change my fuel filter 1 time a year and change my oil around 1.5 times a year depending on miles. So less than $200. Big deal. :R
Not dogging on gas trucks. They work fine. I've towed many miles with them. But for "me", over all, I save money running "my" diesel.