I think the 2011-12 GMC Sierra 1500's come in the 5.3 or .4 Liter and the Sierra Denali comes in the 6.2 I know for sure. The 1500 sticker says 15/21 and the Denali 12/18. I may have seen one that said 13/18 and might have seen a 1500 that said 16/21. Just wondering if it was apples to apples 12/18 vs 15/21 how much of a difference in feul economy might it actually be a difference?

Is it basically what it says, 3 more miles to the gallon on the highway roughly? I wonder how significant I would even notice? I like everything the Denali has but man is it pricey. I sort of wanted to get the 1500 SLT built just like the denali as far as all the woodgrain inside and the front done the same as far as grills and the bumper painted instead of being chrome. Just trying to weigh all of my options and the denali being much more pricey as well as burning more fuel almost makes me want to go with the SLT but I definitely love that interior with the woodgrain. The slt has some woodgrain but not as much as the denali.

 

The difference in fuel economy reflects the difference in engine power. The 5.3 gets better gas mileage than a 6.2. But the 6.2 is more powerful. In my opinion it depends on if you are pulling a trailer for example. The 6.2 will go up hills better. But pulling a trailer will lower your milage even more. The gas mileage figures shown on the vehicle are from test done by the EPA or for the EPA on a dyno not from driving on the streets and highways. Check Consumer Reports or other sources that have done actual road test for a true mileage figure.

 

well one thing i just saw was that the denali's have to run premium as the others call for regular so that in itself might deter me to just get an SLT.

I wonder how many run regular vs just running plus though? I know overall I have heard people say with a vehicle thats anything other than a beater, work truck, something to get from point a to point b, they would run plus instead of regular cause regular has more trash in it. I wonder how much of that matters too if you arent letting the vehicle go past a 1/4 before putting more in as it shouldnt pick up trash if you dont let it go past 1/4 right?