2015 Ram 3500 vs 2015 F350 diesel mpg test

NC Hauler wrote:
I guess the capless fill is something you get use to, I've never had the first issue in filling with small or large pumps. I purchased a rubber cap at Lowes for about $2. Trim it up a little, set it over the fill lip, fits perfectly.. been using it for the last 21 months. Works great, covers the hole and seeing as how the ONLY time it's seen is when one opens the fuel door, I'm not going to spend a pile of money on something that is hidden 95% of the time.


DEF, depends....I've averaged as high as 1500 miles per gallon of DEF to as low as 1100 miles per gallon...(the gage is non-linear and will stay on full for a LONG TIME, but will give you a early warning as to how much further you can drive before you need to re-fill again...I've never gotten to that warning). I get my DEF at a truck stop about 5 miles from my house. Cost $2.69 cents a gallon last time I topped off my tank.

I too have the $2 diesel fuel cap on my truck. I like the feeling that when I fill my DEF, there's no way that stuff can get into my fuel tank. I've had mine since August 2013, first mod I did to my truck LOL.

As for DEF, the easy formula is that for every 100 gallons of diesel burned, you will burn somewhere between 1.5 and 2 gallons of DEF. Our trucks have a 5.5 gallon DEF tank. So whatever your average MPG is, times that by 300 and that's how often you'll be filling your tank roughly. So if I get 18 mpg on average, that means I've filled up my tank about every 5,400 miles which is close to my real life fillup cycle. I have 2 2.5 gallon containers that were used for DEF that I fill up at the truck stop along with my truck to keep a fresh DEF supply at home. Average shelf life of DEF around these parts in my garage would be about 2 years, so I figure a yearly supply of DEF is good enough (10.5 gallons total between the 2 containers and the tank in my truck).