needing help with a v-6 gas problem that gm says is correct

[Dexcam1]

along with other good commits made: Have you changed your oil yet? I have an SS and my milage has always been better than what you are getting. I started around 14.2 mpg.

After first oil change (750 mi) it went up to 15.5 mpg.
2nd oil change (1,500 mi) up to 16.7 mpg.
3rd oil change (2,500 mi) 18 mpg
4th oil change (21,000 mi) was done saturday and I looked today I am at 18.9 mpg.

[spencer489]

Originally Posted by wreeseelkins

I have a 2011 1LT with 1200 miles on it. I am getting horrible mpg (12.1-12.7) I am driving it very easy, no quick starts, no hot rodding, but all in town driving. Traffic is there but not to bad. I have had it at the dealer 2 times now and now the technical assistance for the mechanics are telling me that is all that I can expect. A lot different than the 18 it is rated at...... has anyone else had this problem? Any suggestions on what to do?Thank you!

my first 1200 miles i got 15mpg in the city

[Caspers2SSRS]

Temps have been averaging 90* or above here for weeks..............generally stop and go traffic. Moderate accelleration habits, red light to red light, including hwy entry ramps onto the interstate, speeds there for 20 mile jaunts upwards 80 mph and then back into city patterns...........Cars still averaging 21.9 miles per gallon, 50% city/50% hwy use, and its a SS automatic. Has been since day one..........Thats 28k miles ago . Somethings up OP..................

[AlohaBR]

Okay, just did a small test when I left work tonight. Filled up, had to wait for traffic to turn on the road then had to wait again to make a left, 2 stop signs, 2 red lights and another stop sign. All within 2 miles.
Never exceeded 38 mph, shifted before 2000 rpms and kept it at @1800rpms.
Looked before I entered the freeway, 19.2 avg mpg?
What RPM's are you running at?

[nyrfan]

you defiantly have an issue, here is my test coming home today (I posted this on another thread):

So I installed my MRT 2.0 exhaust on Tuesday night and wanted to see what type of gas mileage I’d be getting. I also have a CAI, CAI, no other mods.
Outside temp about 95, windows open, a/c off, TC & IS off.

Here are the results:

On cruise control for 10 miles at 70mph:


Did a reset when I left the turnpike.

Stop and go traffic for the next 6 miles:


I’m very happy with these results!!

[solo40oz]

So, if I go with the logic of some of the posts on this thread, then the faster I go, the better MPG I will get. So I should just drive 100 mph all the time to achieve best MPG. I understand why some of you think that, but it's not quite accurate.

[AlohaBR]

Will try tomorrow at what you are doing.

[LoneStar]

Originally Posted by solo40oz

So, if I go with the logic of some of the posts on this thread, then the faster I go, the better MPG I will get. So I should just drive 100 mph all the time to achieve best MPG. I understand why some of you think that, but it's not quite accurate.

There is an OPTIMUM speed to get the best gas mileage (~55 mph). Lower speeds and higher speeds net you lower MPG. MPG is a bell-curve as a function of speed.

[ljones]

My avg seed was 18 mph.. 14.7mpg... I've seen it in the 15s at time.

After work i drive with the AC off, windows down and power hole open! I stay about 4/5 miles from work.

[Bonanza7]

Originally Posted by wreeseelkins

I have a 2011 1LT with 1200 miles on it. I am getting horrible mpg (12.1-12.7) I am driving it very easy, no quick starts, no hot rodding, but all in town driving. Traffic is there but not to bad. I have had it at the dealer 2 times now and now the technical assistance for the mechanics are telling me that is all that I can expect. A lot different than the 18 it is rated at...... has anyone else had this problem? Any suggestions on what to do?Thank you!

I am getting 22 in Phoenix, A/C on all the time 50% of the time in sport mode.

[NicksVSix]

This is normal. The V6 gets *nowhere near* its advertised mileage in town/city driving. I burn about 12 litres per 100 km in town but around 7.5 litres on the highway (sorry, you'll have to do the metric = imperial conversions!)

[Angrybird 12]

Originally Posted by ljones

My avg seed was 18 mph.. 14.7mpg... I've seen it in the 15s at time.

After work i drive with the AC off, windows down and power hole open! I stay about 4/5 miles from work.

You are not even driving enough to get the car up to temperature. It will use more gas that way, plus that is hard on your engine. At the average speed and miles you drive I would say you are getting about as good as you can expect. Reset it and get on the interstate and drive for 10 miles at 55 tp 65 mph and check the mileage.

[wreeseelkins]

Originally Posted by AlohaBR

Okay, just did a small test when I left work tonight. Filled up, had to wait for traffic to turn on the road then had to wait again to make a left, 2 stop signs, 2 red lights and another stop sign. All within 2 miles.
Never exceeded 38 mph, shifted before 2000 rpms and kept it at @1800rpms.
Looked before I entered the freeway, 19.2 avg mpg?
What RPM's are you running at?

I normally take off very easy and shift before 2000 rpm. That is alot worse conditions than what I am in, yet still a lot better mileage......GM just called and told me in actual city driving that 12mpg's was what I was going to get although they say 18...... I know my conditions are not as favorable as some, but in the past my cars and suvs have gotten pretty close to what they claim, not this one.

[Chiefish]

Also make sure youre using premium fuel. You might want to do a fuse pull on it as well, i did that with my LS3 and it seemed to help the fuel mileage from 18.2 to 20.8 now, and ive only driven it a short distance since the fuse pull and reset.