Investigation needed in GM Truck MPG

[last truck]

I didn't buy a full size pickup because they said it gets good gas mileage lol.

[SouthernSilveradoGuy85]

I didn't buy a full size pickup because they said it gets good gas mileage lol.

 

I'm sure I said that same thing in my first comment on here lol. For the whole time I've been driving and having my own truck I never looked at gas mileage. I may try to get as much out of it as I could, but never thought too much about it. I mean I first had an '86 Chevy C10 with a 305 and me liking speed I didn't shift when you're supposed to when doing normal driving. I basically redlined it at every shift. Which ironically enough, that's the only truck that didn't have an RPM gauge and it was a manual. The other 2 were/are auto and had/has the RPM gauge lol. Well then I got a '98 Z71 with a 5.7 and 3.73 gears. I was lucky to get double digits in town. Now the '14 which I've gotten used to, but should have seen the grin on my face when I filled up for the first couple of months. I couldn't believe I had a full size 4x4 V8 truck that had no problem getting 16-18 in town (which was way better than my '98 got on the interstate at 95, if I babied the hell out of it I might have gotten 15 out of it) and over 20 on the highway and interstate. To me it's kind of funny if someone complains about the gas mileage on a full size truck. It would be like putting low pro tires that has a 1" sidewall and then complain about the ride. I'm so much of a V8 guy that if I had or felt the need to get a "gas saver" car I would actually get a V8 Camaro and of course I'd always have at least 1 4x4 truck.

[CueBaller]

Mine's not even broken in yet (maybe 1300 miles?), but I'm averaging a little over 20, with a high of 23. This is mostly highway miles, commuting back and forth to work, and the A/C on for most of it (still hot here in the midwest).

[Dnt]

Something is wrong with your truck and something is definitely wrong with your dealer. Did you not read all the posts of people getting 22 mpg's or more on the highway and mid teens around town which is what the sticker says. You need to first find yourself another dealership to look at your truck and then you need to pay attention to your driving style. Not trying to be rude but you are coming off as a troll.

Yes an investigation is needed (into the OP LOL) I am posting a pic of my latest highway mileage below on a 2016 GMC Sierra Denali Crew Cab 6.2 8spd 5800 lb 4x4 Truck. Either something is really wrong with the truck or the OP is a big time troll

 

[tbarn]

You folks do realize that the window sticker mileage is a government test, right? It's not "GM's" numbers. As far as taking it to a dealer, what do you expect them to do? Not much they can. No codes (and these things will set a code if ANYTHING isn't right), check tire pressure, brake drag,operating temp,air filter, that's about it. Just about everything will set a code (high fuel pressure, bad thermostat, trans not shifting into all gears and tcc, etc). You are gonna get what you get for mileage. It's all ball bearings computers and algorithms these days.

[glcbn]

 

It's all ball bearings computers and algorithms these days.

 

As soon as I read that I thought of Fletch.

[Haus_Z71]

It's amazing how much the fuel economy goes down in the winter. I went from a 17-18mpg average to 10!!!!

My highway average is still 20-22, but in the winter I:

1) have lower tire pressure (29 psi). Actually just filled up to 35psi.
2) remote start every morning to warm up.
3) only city driving, which consists of 0-30-0-30-0mph.

*Edit - my last fuel up averaged 10mpg. WTF!! But then I went for a 30 mile highway drive, fueled up, and my highway drive resulted in 21mpg.

 

That city driving on winter gas is a MPG destroyer.

[Dchavis13]

4x4, crew cab, 5.3, 3.42 gears and I was at 18.7mpg on my last tank. 50/50 freeway and city. I'm damn happy.

That is exactly where mine is. I have an early 14 with the same options you state and 6.6 bed. I'm also happy with that.

[SouthernSilveradoGuy85]

I guess some people want a truck that has the ability to haul and tow good size loads while giving the gas mileage of a 4 banger. From what I came from, getting over 20 mpg on any roads with a V8 in a 2 1/2 ton truck made me ecstatic. I guess this is one of those deals where you can say that you have to pay to play. You can't have everything from one vehicle so stop whining and deal with it.

 

I started with an '86 Chevy C10 with a 305 and a "granny" manual transmission so God forbid I had to take the interstate. The trans was L-1-2-3 so imagine having a 4 speed but keeping it in 3rd going 70-75 mph. I also drove it like a race truck so I didn't exactly shift at low RPM to save on gas. I had it from just after turning 17 up until I almost turned 19 so I was heavy footed like always. Then came along a '98 Z71 with a 350 and 3.73 gears. I was lucky to get 14 on the interstate, if I babied it I got 15. Usually got about 9.5-10 mpg in town in the summer. Most was just my driving style and habits. So ya I have no reason to complain about the mileage my '14 gets.

[Camaro45th]

I do decent in my 4.3L. I'm running e85 so I do get the significant drop. But I would still say that I get about 12 mpg mixed, including the remote start.

 

Side note, I pulled my friends boat out of the water the other day, worked like a champ, I cannot complaint about 4.3L. It has worked very well for neon the past few months since I've had it. Looking forward to seeing how it does the snow.

[Havvkeye]

I lost ~3mpg with my heavier tires and 2" level and then with the introduction of winter gas I have lost about 3mpg more and am getting high 13/low 14mpg the last few weeks

[Haus_Z71]

I lost ~3mpg with my heavier tires and 2" level and then with the introduction of winter gas I have lost about 3mpg more and am getting high 13/low 14mpg the last few weeks

 

I would be happy with that! I'm a bit concerned since my city mpg is down to 10mpg. That's stock tires too! I'm going to start using Fuelly to keep track of it.

 

V - LOL there we go. 0.0mpg. That's what it feels like getting 10mpg in a truck that should average 16-18

[Pacfanweb]

Meh, recently took a trip about an hour or so away from home. The 25 mile rolling average was 23.1 on the low side, and 26.3 on the high side. That was mostly highway driving, but some rural back roads, too.

The 50 mile rolling average was 21-23. Closer together, but you'd expect that.

 

The only way I get 16-ish on the low side is if I sit and idle a lot.

 

This is a 2015 Sierra with the 5.3.

 

By comparison, my 04 Suburban with an 05 LQ9 6.0 in it got 17 mph on a trip to NY this past June.

I was actually pretty happy about that, so I'm ecstatic about a pickup that gets over 20 on the road.

[powerhaulic]

currently watching the 400mi average

18.3mpg

23.3 peak

275/50-20 Michelin Defenders

full 3.5" exhaust w/ 22" magnaflow

Airaid MIT K&N drop in

no tune yet

[Dnt]

Update on mileage. Truck = 2016 Denali 6.2 8spd 3.23 rear end currently has 11,0000 on the truck. Mods GM Borla catback (dealer installed) dual exhaust / Cold Air Intake CAI / Peragon bed cover / HyperTech max energy 2.0 part 2000 / Tier 1 93 octane fuel except for last couple of tanks currently doing a 87 octane test.

Important to note the engine hours. On the Denali dash the average speed is calculated from ALL the time while engine is running. Remote start / city driving / idling time that is why the overall average speed is very low.

Hopefully the OP has resolved his issues by now.........he is a grumpy son of gun that is for sure. I would hate to be his service advisor at the dealership I bet those guys run and hide when they see him pull up LOL.