Bikewhisperer

Tires were fine and I was 70 percent hwy. I towed a 6x12 enclosed trailer once for 100 miles and got 6mpg. Sent from my SGH-I337M using Tapatalk

You can't just blame driving style. I had a 5.3 with 3.08 gears and my lifetime over 9000 miles was 14mpg. I would drive with the full intention of getting the best fuel economy possible, but it just wouldn't do it. It did have some good moments here and there, but when I went to a diesel 2500 I broke all my mpg records from that 1500. It's a shitty problem to have because the dealers won't help out because it's easy to blame driving style. Sent from my SGH-I337M using Tapatalk

Monday. It sure feels Iike a truck with the 4 or so inches higher and the stiffer ride. Got 18mpg on the drive to town this morning. Woot! Don't get me wrong, I know the truck costs more and the maintenance is more. I'm not thinking this will cost me less long term, but I made a sacrifice in usability with the last truck for fuel economy and was keeping my old 2500 for heavy stuff. Now I can sell it. Sent from my SGH-I337M using Tapatalk

I got tired of the uphill battle with my fuel economy and basically got a buy back and got the 2015 2500 denali. Getting 3mpg better than my 2014 with 3.08 gears after the first 250 miles. Sent from my SGH-I337M using Tapatalk

Same here, like a yoyo. I'd say I'm 1mpg better than you though. Sent from my SGH-I337M using Tapatalk

I should mention I took that diesel out for a drive again today. Drove it home in the country and back again, did a bit of running around in town. It was 15mpg, 1mpg better than mine according to DIC. Sent from my SGH-I337M using Tapatalk

I've seen huge increases since it's above freezing. Getting 650kms (400 miles) out of a tank instead of 550kms (340 miles). It seems so finicky Sent from my SGH-I337M using Tapatalk

Pretty much exactly, it was mostly highway. Sent from my SGH-I337M using Tapatalk

I just test drove a 2015 diesel for 35 miles, then took my broken in 2014 1/2 ton with 3.08 on the exact route. Got the same mileage according to the DIC. Sent from my SGH-I337M using Tapatalk

I rarely reset mine, it's always just showing the last 25 miles anyway. With the recall all of my bests were reset. The 25 mile looked really good and got a best of 18mpg on the way home, above freezing temps and driving like a grandma, but has settled back to about 14mpg after driving 120 miles or so after the update. Similar to when I first got it, fuel economy went gradually downhill. I get worse on the highway than in the city as most of my city driving is freeway. Sent from my SGH-I337M using Tapatalk

I've gone back to 87 octane after 12 or so tanks of shell premium with no better fuel economy. Just got the fire update yesterday so I'm curious to see if there is any difference, but the weather also turned warm so it will be hard to say if it was the update or the weather if fuel economy is better. Lifetime of 14mpg with 11000kms, 75 ‰ highway. Dealership now agrees it's broken in and something seems wrong. Sent from my SGH-I337M using Tapatalk

Same here, same roads same conditions. It ridiculous! I wonder if a flashscan tune could fix this if Gm can't? A friend has a 2013 and it acts the same way, just not as extreme swings. Sent from my SGH-I337M using Tapatalk

Did you get an answer back?

I mean taken out of drive, not 4x4. Oops Sent from my SGH-I747M using Tapatalk

If it's taken out of auto it refuses to go into v4 unless left if m6, which seems to act just like auto if you ask me. Mine anyway, yours different? Sent from my SGH-I747M using Tapatalk

It below freezing half the year up here. I don't want 13mpg half the time. I'm pretty envious of some of the numbers I see here. Sent from my SGH-I747M using Tapatalk

Karnut: where are you located and what kind of temps you experiencing? I'm in Saskatoon with a lot of -20c highs, but rarely warming up as I park in heated garage at home and work, 70/30 hwy/city, and my lifetime is 14mpg with 4500 miles on it. Best tank was my second one. Light foot as I'm striving for better. Sent from my SGH-I747M using Tapatalk

I'm thinking of doing the same thing when it's in this week. I average 13.5 not letting the tach over 2k. If I drove it like I'd like, not bagging it, I'd get the same as my 2005 3/4 ton. Sent from my SGH-I747M using Tapatalk

In it's defense, the side wind was brutal, about 50mph. But ya, my 2005 6.0 would get better in those conditions.

Stock 275/55/20 5.3-3.08 6x12 enclosed trailer weighing appx 2000 - 2500 pounds in nasty side wind, -20c 7.64mpg at 55mph

I've been checking my hand calcs against the DIC and they are surprisingly damn close. I not happy with my fuel consumption at all though. I have been making it a mission to beat my best records on the DIC by basically driving like an old lady everywhere I go for the last while, and I mean seriously babying it, and I can't seem to get anywhere near the numbers I am seeing some people getting. SLT 5.3 with the 3.08 gears. A little more than 50% of my daily driving is highway rarely over 65. The only time I can get my numbers down is on the freeway at 50, then the instant is great! There has been some crazy cold weather (-30 and colder) but alot of nice above freezing days as well. Usually parked in heated garage so warming up is minimal. 12.02 First fill 16.63 highway trip at 60-75mph 11.94 12.39 12.24 7.64 towing 2000 pound enclosed trailer in a blizzard on highway, high side wind. 14.84 good highway conditions at 65 14.53 14.24 started with premium from here on 13.42 12.91 14.95 15.75 13.71 Most recent 5444kms Average lifetime 13.28 mpg or 17.71 l/100kms (17.4 lifetime according to onstar) 5444kms on vehicle Best ever 25 mile 18.52 mpg ot 12.7 l/100kms Anyone else from the cold north getting numbers this low? I expected a hell of alot better.