As long as diesel drivers insist on keeping up with the traffic in the left lane, no matter what they drive or tow, their MPG will never be more than 2-3 MPG better than an otherwise identical gasoline-fueled combo.
And who can fairly care about MPG observed under normal conditions? If you really care about MPG, you drive for MPG, no matter how many one-finger salutes it gets you. They aren't paying for your gas, they have no right to ask you to waste it just because they're in a selfish and illegal hurry.
When you drive for MPG, you will get better MPG than what you saw on your window sticker. If not, your driving style is wrong, the vehicle's tune / maintenance is wrong, or you made mods that are wrong.
My own diesel was EPA-rated to do 31 MPG. Nobody ever got that, because nobody ever drove smart, like the EPA scientists. The gasoline alternative was rated around 65-75% of that MPG, so diesel can do the MPG you should expect it to do.
It still comes back to drag, and it increases exponentially. So the more you start with, the more it hurts you to go another 5 MPH faster. Then yet another 5 MPH faster.
You want MPG, then never again exceed 55 MPH. This is legal on every interstate in America. And the only reason we even have minimum speed limits is for the wealthy to enjoy the costly luxury of going 75.
I'm running out of different ways to elaborate on this. Y'all are wasting fuel that I'm gonna need long after all y'all have switched from oil-based fuels.
'06 GMC C2500HD RCLB gasser 4.10:1, 4L80E, custom camshaft
'84 Trans Am 6.2 diesel, 700R-4, custom Class-3 receiver
'69 F350 dually. GM 6.2 diesel, turbo, 700R-4, NP208 all pending.
whisperide wrote: As long as diesel drivers insist on keeping up with the traffic in the left lane, no matter what they drive or tow, their MPG will never be more than 2-3 MPG better than an otherwise identical gasoline-fueled combo.
And who can fairly care about MPG observed under normal conditions? If you really care about MPG, you drive for MPG, no matter how many one-finger salutes it gets you. They aren't paying for your gas, they have no right to ask you to waste it just because they're in a selfish and illegal hurry.
When you drive for MPG, you will get better MPG than what you saw on your window sticker. If not, your driving style is wrong, the vehicle's tune / maintenance is wrong, or you made mods that are wrong.
My own diesel was EPA-rated to do 31 MPG. Nobody ever got that, because nobody ever drove smart, like the EPA scientists. The gasoline alternative was rated around 65-75% of that MPG, so diesel can do the MPG you should expect it to do.
It still comes back to drag, and it increases exponentially. So the more you start with, the more it hurts you to go another 5 MPH faster. Then yet another 5 MPH faster.
You want MPG, then never again exceed 55 MPH. This is legal on every interstate in America. And the only reason we even have minimum speed limits is for the wealthy to enjoy the costly luxury of going 75.
I'm running out of different ways to elaborate on this. Y'all are wasting fuel that I'm gonna need long after all y'all have switched from oil-based fuels.
The rare enough quality of paying attention is on display to good effect, here.
We get a little over 21 mpg empty (or pulling a '74 popup camper) but the truck isn't really broken in yet. Better fuel economy, such as it is, gives us a better range. It's pretty good for a brick I guess. (2012 F350 SRW 4WD crewcab shortbed 3.55 axle ratio)
This is an interesting video. It is a bit of a rant and some of the conversions and numbers are a little whacky but it is kinda interesting.
I know new diesel smart cars (no longer available in North America) are getting solid mid 80's for mileage but the 450 generation (up to 2007 like ours) still averages around around mid 70's US mpg. As far as I know though the North American Jetta TDI's are still getting around mid 50's to 60 mpg US and they are a practical 4 seat vehicle (albeit boring with no convertible option
I get really bad fuel mileage . . . . 10 when towing a 14000 5th wheel, and 13 mpg around town. I have 3.56 gear ratio, and 4*4. My Ford F350 truck is over 8000 pounds.
I didn't buy a diesel truck for the good mileage . . . . I bought the diesel for towing.
I don't know how anyone gets good fuel mileage driving a big diesel truck and heavy trailer.
Word of Caution . . . . ST trailer tires are rated for only 65 MPH. If you have ST tires and are close to weight limits, you may not want to go over 60 MPH . AND . . . . keep the trailer tires at max rated air pressure, not more nor less.
My guess is that trailer tire blowouts are caused by crappy China made tires, low air pressure, and high speed.
ken
2011 Ford F-350 6.7 diesel, Crew Cab, LB, SRW, 4X4, White
Cedar Creek 34SB, 37 feet 5th wheel, Reese 20K Hitch
"So many questions, so little time."
2oldman wrote: I don't know if the 'better mileage' with diesel is a myth or if there's any basis in fact to this.
You have got to be kidding. Read the mileage of people hauling 3000-5000 lb. campers with the same model trucks and compare the mileage they report with their gas or diesel engine powered ones. The people with the diesel trucks get 30% more MPG on average.
The other benefit is greater range on a tank of fuel. With my truck's 36 gallon tank I can go 34 x 20 or 680 miles with the truck empty or 34 x 14.5 or 493 miles with the TC in the back. With a gas engine I would have a range or 510/340 miles at best.
The diesel engine also provides twice the torque of the gas engine and it does so at 1600 RPM whereas the gas engine peaks at 4200 RPM. Much easier to stay in the 1600 RPM power band going up a grade without lots of downshifting and a lot more power to pass a slower truck and so so safely.
Gas engines are less efficient than gas engines and this is compounded by their need to operate at higher RPM's where there is more power loss from internal friction. The 6-speed transmissions help but not enough to offset the higher efficiency of diesel engines (which is why they are used for commercial, marine, and military vehicles).
Going downhill the higher compression of the diesel provides better engine braking and with the diesel there is also the exhaust brake which minimizes wear on the truck's brakes and on the driver's nerves.
My fuel costs per mile are only slighter better with diesel than with gas and my maintenance costs are no different. I might have paid more to buy the new truck with the diesel engine but in point of fact I paid less than what most people have paid for the same truck with the gas engine.
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