Just finished up a 525 mile round trip from MA to NJ 2016 3.5L Lariat. 36 gallon tank.

Hand calculated 20.4 MPG during the trip which was two adults and a packed truck heading down and three adults and a packed truck heading back up.

Filled up at BJs with 50 miles on the DTE. $1.889 per gallon for 32.56 gallons. After fillup Ive never seen my DTE so high and I know I'm not really going to get 790 miles out of the new tank, but why so high?

 

Math.

36 gallons x 20.4 = 734, but DTE takes most recent mpg.

790 / 36 = 21.94. Your most recent mpg bars should be around 22 mpg.

 

I'd like to know what the DTE on the 2.7 w/ 36 gallon tank is like highway driving.

 

Same math.

If your most recent MPG is say 24mpg, it will say 864. They will never go over 999 though.