Most Efficient .5 Ton While Towing

There’s a little merit to the don’t top off the tank argument if you have a defective evap system. Otherwise it doesn’t hurt anything.
But you might should seek professional counseling if your world revolves around exactly what how and how much to top off your gas tank.....

Cummins12V98 wrote:
Ridiculous way to SUPPOSEDLY fill all their tanks the same. So take those numbers with a grain!

Three different drivers and fuel tank fillers, HMMMMM.

So people say Diesels are expensive to operate, REALLY??? 91 octane is well north of Diesel pricing.

Little trailer like that and they can't get over 9.8? Flat land towing like that I would get 10.5 at 33k combined.

I guess that depends on what prices are in your area. It's not unusual here in truck country for Premium fuel (93 octane) to be less expensive than Diesel. Last I checked Diesel was an 80 cent premium over regular, and typically I see a 40-50 cent premium for 93 over regular. Don't forget the DEF.

None of which matters if you are towing heavy enough to need or want diesel.

ib516 wrote:

Cummins12V98 wrote:

TurnThePage wrote:
Isn't that what they do?

If you are referring to how the fuel fill is done, NO. They have nozzle in tank with full force when it clicks they wait 30 seconds the blast again til it clicks. They do this before they do the test run and after to determine gallons used.

NOT very Scientific IMHO.

The FACT they used three different people to do the fill and test drive is NOT very Scientific IMHO.

Filling the tank to the top is more likely to cause a very expensive repair by filling the evap system with liquid gas. Again, RTFM. Time and time again folks are advised not to "top off" when filling with gas.

Very good point. My Ford user guide specifically states to only allow two auto click-offs when refueling, page 389. So Ford sees filling it up to the top is a not recommended.

And on page 637 of the 2015 Ram owners manual, it states basically the same. After the nozzle clicks, the tank is full.

VernDiesel wrote:
...As mentioned Trailer Life magazine averaged 14.77 mpg useing the 3.0 diesel with a similar trailer & weight but I’ll bet at 65. My Ram ED (tuned) would have averaged in the 15s with that trailer/weight but at 65. Fuelie is a good overall comparison source. Not sure what I would have lost to dragging it at 70.

The difference between 70mph and 65mph is 9% less efficiency. While it will save you 32 minutes over a 500 mile drive it will cost -1.2mpg.

"Filling the tank to the top is more likely to cause a very expensive repair by filling the evap system with liquid gas. Again, RTFM. Time and time again folks are advised not to "top off" when filling with gas."

NEVER heard of such a thing. No topping off is so GOD forbid some hits the ground.

I have filled to the top on every vehicle I have owned gas or diesel since 1974. Right or wrong never had an issue.

1320Fastback wrote:
Leaving on a three week cross country trip tomorrow and plan to fill tank to the second automatic shut off every time and hand calculate using GPS milage. Will not post results but should be pretty accurate.

Why wouldn't you simply fill the BIG open hole to the top???

"Will not post results but should be pretty accurate."

WHAT does the above mean???

GPS part is a good idea or simply determine if your odo is off and adjust mileage accordingly. I always added 5% to the mileage on my 98. My 15 is right on the money.

Not that it matters but they did use 91 octane in the GMC as well.

I think their fill method is as good as its going to get, they do use the same gas pump for filling the trucks before and after each test. Like ib516 said above you can cause damage by overfilling your tank, I always stop when it clicks off the first time.

Cummins12V98 wrote:

TurnThePage wrote:
Isn't that what they do?

If you are referring to how the fuel fill is done, NO. They have nozzle in tank with full force when it clicks they wait 30 seconds the blast again til it clicks. They do this before they do the test run and after to determine gallons used.

NOT very Scientific IMHO.

The FACT they used three different people to do the fill and test drive is NOT very Scientific IMHO.

Filling the tank to the top is more likely to cause a very expensive repair by filling the evap system with liquid gas. Again, RTFM. Time and time again folks are advised not to "top off" when filling with gas.

Keep in mind they ran this test at 70 mph which hurts mileage dragging a 7k enclosed trailer. Drag kills mileage. 65 mph would have been a better overall speed to use for comparison IMO. Still 9.7, 9.2, & the thirsty EB at 8.7 suck for towing economy.

As mentioned Trailer Life magazine averaged 14.77 mpg useing the 3.0 diesel with a similar trailer & weight but I’ll bet at 65. My Ram ED (tuned) would have averaged in the 15s with that trailer/weight but at 65. Fuelie is a good overall comparison source. Not sure what I would have lost to dragging it at 70. Our company big 3 diesels (6.6/7 liter) tuned & stock size tires have taken about 20 percent more fuel when run with my truck until you start to push the ED then that gap thins. That would be in the 12s still a big gap over the gas trucks and a larger heavier more capable truck to boot.

Not knocking gassers both gas & diesels have pros & cons just looking at towing economy.

My lil 26 gallon tank routinely takes double axle TTs 350 miles from Dayton OH to St Louis MO. Bigger tank would give more option in cross country fueling but after the over 5 hours it takes I’m ready to get out of the cab. How much does it cost to change the timing belt every 150,000 miles per Ford?

goducks10 wrote:

VernDiesel wrote:
The new 3.0 liter F-150 diesel would have swept the field. Should average 13 or 14 mpg for this test.

Latest issue of Trailer Life Magazine has the F150 3.0 towing a Lance 2465 that weighs loaded up for the test @6790 lbs.
They got 14.77 mpg towing and 25.64 non towing.
Towing was in the wine country in CA so not just a flat road somewhere.
Biggest issue with the F150 3.0 IMO is the fact that you have to get the Larait or higher trim package to get the 3.0. It's not even there in the XLT.

A bigger issue to me is that you can't get it with the 36 gallon tank. It only comes with the small tank.

The 3.0 also has a timing belt...no thanks.