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What gas mileage are you getting?

120862 Views 232 Replies 141 Participants Last post by  08-2.4l dave
Im just about through my first tank, and I only got about 17 MPG with some highway and soem city, not getting on it at all....

What kind of mileage are you getting and how many miles are on your car, i think mine just needs to be broken in, im only at 150 miles....
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Wow Ive never had that good of MPG, ive had mine stock forever, and get about 16mpg I drive on the freeway and some street but mostly during really busy traffic hours... so maybe that has something to do with it
I commute daily on the Highway... and I don't baby it. Been seeing about 23-24mpg recently...
My 29-31mpg highway is also staying under 70mph. I also check my tire pressure once a week
just got my tires, checked pressure and still average about 17 mpg... but average speed was 23mph
I've only filled up twice on my current G6 and my average is about 25.4

On my old G6, which was a non-GT, I averaged about 24, but I also had a much shorter commute. My new commute is about 80/20 highway/town, the old one was about 50/50.
In my 2005 3.5L with a CRABs CAI, i average about 24.5 city and 55 combined. If im on an all highway trip i get about 27-28 mpg overall.
Getting less than 380kms out of a full tank of gas. 60% city driving and 30% highway driving.. anyone know why i have terrible gas mileage?
Getting less than 380kms out of a full tank of gas. 60% city driving and 30% highway driving.. anyone know why i have terrible gas mileage?
City driving is your culprit, especially if you have the V6. There are several factors that you have to consider such as:

Tire pressure (check at least once a week)
Speed
Acceleration to get up to speed & passing.
Weight in the vehicle
Air filter relatively clean - no rodent nests, etc
Fluids are changed regularly (12,000kms on cheap engine oil can increase engine friction which can lead to increased fuel use)
Heat - driving in traffic will make the cooling fans come on more often, heat is the main enemy of all engine components


Just to elaborate on tire pressure, some tiers for the G6 with higher speed ratings use upwards of 50psi, versus the stock 30-34psi setting. Running tires more than 5psi under their maximum will increase drag and can affect handling. I have V rated General UHP tires which are rated at 50psi, but I want a compromise with ride comfort and handling so I set them at 44psi. Most shops, after a service will lower them down to 30-32psi as per the door sticker, because the OEM Continental tires had a max of 35psi.

I don't recommend over inflating tires as it can prematurely bald the centre portion of the tread. In the hopes of better fuel economy (most of the time it will net 1-2mpg increase) is to take 35psi tires, and inflate them to 40psi, which in turn after a trip on the highway will warm up so they read 44psi. Handling then goes out the door, along with braking performance as the tread contact patch is limited. Just food for thought.
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I have switched to Mid-Grade gas and went from 23 MPG to almost 27 MPG. I normally don't drive like granny either. Other than normal maintenance (new brake pads, etc.), that's the only thing I've changed recently.
Been driving my G6 for about 3 weeks on and off. A few days in the city and 10.7L/100 km in the city, and all highway is 8.5L/100km, then my DTE Says 705 km.


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Been driving my G6 for about 3 weeks on and off. A few days in the city and 10.7L/100 km in the city, and all highway is 8.5L/100km, then my DTE Says 705 km.


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damn what sort of maintenance did you do to your car? my car reads 500km when i pump it with 87 but that thing is flimsy.. i only get around 350km a tank 60%city/40%highway which is terrible.. how much kms do you get out of a tank?
I drive too much of a combo of hwy and city to give good real #'s, but the average seems to be 22mpg, BUT I do notice that midgrade seems to give me the best mileage for my $.

Low end gas burns up too quick and premium is almost a waste of $. I try to pretty much stick with one grade of gas anyway to keep it running smooth.

Also, yes, as many said- tire pressure for sure and all other maintenance. The more you can drive highway only, the better your mileage is going to get for your $.
Well unfortunately I have yet to fill it, but I filled up on side of a highway and then did a night drive from 9:30-2:30 so it was cooler at night, otherwise it's how ever the dealer had it tuned up. I haven't pulled any plugs or anything yet to see what it looks like. I'll try and get a pic of the DIC when it shows this km's on there, maybe this Tuesday coming up.


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^^ my numbers were posted with 98% highway. Just a few city stops to get snacks and washroom breaks for the girls.


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I have switched to Mid-Grade gas and went from 23 MPG to almost 27 MPG. I normally don't drive like granny either. Other than normal maintenance (new brake pads, etc.), that's the only thing I've changed recently.
Higher octane gas really makes a difference? I always read it didn't, and the owners manual says 87 octane so that's what I always use. I should try it.

I usually get about 23.5 to 25.5 mpg depending on how hot it is and how much the AC is on. I travel 50/50 highway/city usually. It's not bad considering my last car never got above 18mpg. Still I would like better. I hear the cold air intake helps.
After putting in the transmission cooler this weekend, took it out on a 12 hour drive as well. Got a whopping 7.7 L/100 kms on the flat part of the highway, 8.7 with a little more load and rolly mins and 9.8 going up steep hills. The total DTE by the end was 630 kms driven.


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I have yet to drive long enough to actually see this, but filled up and went to go see my gauge, and this is what it showed. Electronics Technology Vehicle Vehicle audio Car



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I have yet to drive long enough to actually see this, but filled up and went to go see my gauge, and this is what it showed. View attachment 5433


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damn that is good..the highest my car recently got on the display was 600km but on a long road trip..but the tank i have now in my car only got 220kms from full to half tank which is pathetic for a 65L gas tank.. did you do anything to your car? what maintenance repairs have you done? let me know!!
I've done nothing but pop in a K&N replacement air filter and used some Bosch fine wire iridium plugs. Haven't even done the throttle body clean yet either.
Maybe I got lucky and the previous owner(first owner) broke it in good and so now I'm reaping the benifits of it.
I don't drive it to work, its more of a pleasure vehicle so for now its like 90% highway and 10%in city/drive to work.


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