Ok I know you gotta pay to play and a 6.2 truck isn't exactly what anyone should be looking at if the want descent mpg. That said I am interested in real world results. I have owned two 6.2 trucks and mpg varied greatly. 2011 GMC All Terrain 6.2 4x4 342 got on average 17.5 and 20 on a cross country trip. 2013 Chevy 6.2 max tow 4x4 373 got on average 14. I drive mostly highway 60-75 and do 55 miles a day so gas mileage can play a big role in my budget. Driving a 2014 mustang gt now getting 20-21. I don't think I will see that but above 18 would be nice. Considering getting back in a 4x4 crew 6.2 and would like as much info as possible. Thanks!

 

huge difference between those two trucks,014 has to be a step up in mileage

 

For the 3600 miles my 6.2 has on it, it has averaged 18.9 overall mileage. That also included pulling a 12' trailer w/700 lb load 800 mi. The last tank went 507 miles & averaged 22.0 mpg. This tank has 300+ miles & is at 21.2 mpg with more town driving. Best 25 mi avg is 27.5 mpg, best 400 mi is 22.2 mpg, all according to the DIC. I am well pleased with it so far...

 

Thanks for posting up. I traded out of that max tow 6.2 in less than 8 months due to the mileage. I liked the 373 gear around town but if that made the big mpg difference out on the highway i will stay 342 in the future. Did not expect that big of a difference.

 

this has been very consistent with my results as well..

and I have something to add with my experiences, I seem to get pretty consistently 23 MPG averaging 75-80 mph on the highway.
but what's really interesting I have easily got as much as 30 mpg in town if im always rolling mainly due to the fact we don't have a ton of stop and go traffic where I live. if I am on a major artery through town with minimal stops I can get better MPG but in downtown area I get about 17-18 mpg.

I towed a trailer with 4 dirt bikes 4 guys in the truck and 4 bags of gear in the bed. our trip took us a total of 331 miles and we averaged 15.5 mpg over the continental divide from Colorado springs to Grand junction Colorado. considering we were hauling about 4,000 worth of gear and guys, driving +5 over the posted speed limit and over mountain passes I felt that was quite respectable.

the same route with no trailer and only 3 bikes and gear in the bed got us 20 mpg on a different trip.
my 2009 Toyota Tacoma used to get 19 MPG on a good day and without hauling anything at all! the fact a truck with 2x the capability (and weight) and getting better MPG to me is nothing short of awesome.

 

Good news. Thanks. A new 6.2 sounds promising. Might be a few months for me but i'm putting together my short list of stuff to look at. Have to catch up some negative equity before doing anything.

 

My brother Lance's truck on a 1,000 mile round trip averaged 18.9 or 19.2. It's 2014 6.2 with 3.73's. Pretty impressive compared to my 2011 6.2 that gets 16.5 on the same trip.

 

not bad with the 373s. my 13 6.2 4x4 with 373s never saw over 17 and usually got 14. that gives me hope for a 6.2 with 342s. thanks.

 

i used to get some really good mileage when the truck was new and stock(19-20). but before i recently sold it, my 12 6.2 4x4 w/3.73s would average 14-16mpg overall. can't wait for better mileage with the new truck. 3 more long weeks..

 

2010 Escalade, I am seriously lucky to get 13 in town. Towing my snowmobile trailer (little clam shell for 2) I get high 13's. I haven't driven more than 80mi at a pop without old man winter though so I expect much higher numbers once I get that opportunity.