Hello, so I’ve been reading about the mileage debate and all the other things on this forum and all points are valid on mpg. I’ve owned all three engines in some form from Gm. By far I like my 22 3.0 refresh the best. My mpg from my 15 6.2 high country is better on highway by about 8.5 to 9 mpg at almost 30 compared to 21 with 6.2. No question the 6.2 has way more top end and passing power but 3.0 is low end monster and way smother to drive. Had issues with 6.2 dropping lifters 2 times , 2nd time was within 1200 miles of first repair. After that I decided to go duramax. So far it’s been amazing. Mileage dips a little with winter blend fuel but still better then 6.2 and way better then same year 5.3 that my friend owns. So it’s really about preference I’d say. Hoping for better reliability than before but I do miss the gritty up and go of 6.2 lol.