from iowa to pennsylvania no problems and got 18.5 mpg at 70 mph i love this motor just had to share

 

Me and my sis's fiance took his Duramax from n.w. Ohio to Atlanta and back this weekend and averaged 20 at 80 mph...but I had to drive a Chevy so I was still dissapointed, lol. I ran my truck from here to Chicago and back last year and didnt have to fill up till around Fort Wayne on the way back, didn't think to keep track of mileage but I think the old girl did decent.

 

My family just got back from a trip pulling our 26' travel trailer and averaged 13.7 over a 1000 miles and multiple tanks of fuel. Would have done a little better, but I ran 65-70 on the return trip so mileage dropped a little. On the way I kept speed below 65 and got over 14. I am really happy because Suburban we used to tow with would not have gotten over 10mpg.

 

I normally get 17.1mpg on the overhead monitor. Yes, I know it's not completely accurate. I removed the Quad XZT+ (timing only mode) and everything else equal it's now reading 17.5 driving the same route back/forth to work unloaded. Not to highjack the thread but any ideas why this would change?

 

well i just got back got an average of 22mpg at 65mph (hand calculated) took a diffrent route home

 

Just did my first road trip and with the truck stuffed with people and gear including an atv @70 mph for about 1400 miles, averaged 19-20 mpg. I can do much better light and slower @ about 50 mph. Had a hugh headwind for the last 300 miles.

 

recently added a pipe to my exhaust to make it duals, & put in a #10 plate. Boy what a difference!
I hand calculated a tankful of mixed driving- city & hwy empty, & pulling my 24' lawn trailer- prob 4400# total. got about 650 miles to a tank! figures out roughly 19 mpg of mixed driving & towing! I am thrilled. Before it was a bit out of time & I only got about 13 in town & 17 highway without a trailer.....