6.6 Chevy gas engine

Sjm9911 wrote:

blt2ski wrote:

LanceRKeys wrote:

ksss wrote:
My brother just picked up his GMC Denali 3500 SRW, CC/SB with the 6.6 gas. Traveling across parts of Eastern North Dakota, we got 14-15 mpg on flat roads empty. This truck would need quite a tail wind to hit 20 mpg. Very nice pickup though.

Note that the claimed 20mpg was with the cruise set below 60mph.

Considering the 1500's with the same basic motor can get 21-22 mpg. IF some of the same options like 3.42 gears, 10 sp trans, cylinder shutoff were available options, 20 mpg should be doable on a long term level ground. Assuming you are not headed into a 15-20 mph headwind or other known hit to mpg.

My swag is this is not going to happen anytime soon in the over 8400 gvw 8 lug pickups.

Marty

Its not a 1500 though, the bed is longer the height of the truck is way taller. It weighs more. I cant see it hitting that mph with the same basic motor.

We had cruise set at 65, it was all two lane road, no Interstate. I don't see 20 mpg possible without going down hill and or a serious tail wind. We bucked some wind, and were down to 11-12 at times. There is way too much pickup there to get 20 mpg. It will be interesting to see what happens when they drop the 10 speed in it. Heck, if you could get a reliable 18 mpg, with an HD gas that would be a huge accomplishment. I really don't think that is possible from any HD gas engine from any OEM.