i was at the gas station the other day filling up and and other 15 showed up with the same engine as me 5.0
we got talking about the DTE mileage after a fill up
mine was saying 636 km and he said his showed 999 and he says he often gets 999, i've never seen 999, the closest to that number was 825 when i 1st picked up the truck the dealership had filled up the tank
here in canada we only get the 1 tank 36g/136l, unlike our cousin down south witch you guys get regular or extended tank the one we get
so how is DTE calculated?

 

This is probably the most vague answer ever, but I'm pretty sure it determines your 'Miles to Empty' based on your 'Average MPG'. And that's why that number will ultimately vary.

 

I'm in Manitoba and whenever I fill up the 136L tank, the DTE always reads 999. It will sit there for a very long time. There's been times when it doesn't move for 200 kms before it starts.

 

I think that you are correct. It's a big difference, but based on the info in icer's signature, with the lift, big tires, etc., it could add up.

 

It's based on the last 500 miles driven, posted many times. Says so in your m-a-n-u-a-l.

 

It seems to use your average mpg in the last few minutes. But mine isn't all that accurate. Or is it? Coming home from Chicago a few weeks ago the GPS showed 245 miles to my house the DTE showed 245 miles. I had to stop to buy gas when the light came on about 45 miles from my house. So maybe I could of made it home with the reserve in the tank but at 2:00 am I wasn't going to try. Took 32.5 to top off the tank.

But at the time I checked the 245 miles I had been driving at 60 mph where I get good mileage after that speed went up to 74 mph where it starts to drop off quickly. So this might explain what happened. Still a nice feature and makes driving the truck even more fun.

So DTE means what it says I guess EMPTY! Was interesting watching the GPS's distance to go dropping slower than the tanks DTE's no mater how carefully I drove trying to get the best mileage. I really thought it would be the other way around after driving around the city for two days in all that stop and go traffic.

But still was nice to drive there and almost home on one tank.

Still miss the good old days with dual tanks! But not the poor mileage back then.