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Discussion Starter #1
My wife gives me sh*t every time I have to fill up. She drives a CTS and wonders why I have to fill up more often than her? Anyway I was trying to get the best possible MPG and so far I can only get 16MPG? It's city driving mostly, some highway. WTF Is it me or the car. I have got better than this but latley no way. A couple of tanks ago I checked the computer and I got an average of 11MPG!!:willy: I think I have a heavy foot, but dam, for the past couple of day I have been driving like a 90 year old and still I can only get 16!!! What say you?
 

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If you're in stop and go conditions a lot, you'll never get decent mileage. If you drive an automatic -- same deal.

However, if you're driving an M6 and are getting that kind of mileage -- you either have a heavy foot, a hole in your gas tank, or your wife is siphoning gas out of your car to top hers off.

The owner's manual contains the ideal shift points for the GTO -- from an economy standpoint. For the '04, they are:

First Gear: 0 - 15
Second: 16 - 22
Third: 23-30
Fourth: 31-40
Fifth: 41-50
Sixth: 51 and up

Real fun, huh? Those shift points are something like 1500 RPM -- so that will give you an idea of just how limiting they are. You've 5.7 to 6.0 litres of space to fill -- so it's going to consume a lot of gas if you get any RPMs going at all.

Beyond the shift points, if you have a manual, you can do stuff like coast downhill or coast up to stoplights, etc. But nothing raises your overall MPG like a nice freeway trip. In my '04, I'm able to get around 17 MPG city -- but that's using every trick in the book.

Also, depending on where you live -- the formulation of "winter gas" may be such that your mileage gets taken down a couple of points.
 

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The best I can get in my 05 M6 here in traffic from altamonte springs to orlando is 13-14 mpg and that's doing the 2,4,6 shift and keeping the rmps below 2K. If I hammer it then i get around 11 mpg. My wife gets 13mpg in her Navigator.
 

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Oddly enough I've found that shifting around 2800-3000 when I had mine (stock) netted the best economy (18 mpg), Danielle (the current owner) is consistently seeing 19.5 mpg with medium amounts of stop and go traffic, the mpg is there your just shifting in the wrong rpm (which I understand that shifting at a higher rpm looks like you'll be using more fuel, but, trust me and try it).:cheers
 

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Discussion Starter #6
I guess I'm not the only one! Thanks for your input. I will check the manual for the shift points for fuel economy. That's what I thought as well DEALER. The way I understood it was dont shift too soon, otherwise you will bog the motor and it will suck more fuel rather than shift at 3 grand. I'll give it a shot. Thanks again.:cool
 

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05_HUMBLER said:
I guess I'm not the only one! Thanks for your input. I will check the manual for the shift points for fuel economy. That's what I thought as well DEALER. The way I understood it was dont shift too soon, otherwise you will bog the motor and it will suck more fuel rather than shift at 3 grand. I'll give it a shot. Thanks again.:cool
No problem, hope it helps!:cheers
 

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GTODEALER said:
Oddly enough I've found that shifting around 2800-3000 when I had mine (stock) netted the best economy (18 mpg), Danielle (the current owner) is consistently seeing 19.5 mpg with medium amounts of stop and go traffic, the mpg is there your just shifting in the wrong rpm (which I understand that shifting at a higher rpm looks like you'll be using more fuel, but, trust me and try it).:cheers

:agree

Shifting around 2500 for me nets the largest gains.
 

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Hmm.. i'll try that with a new tank of Gas. This is the first Manual V8 i've had. All my other manuals were 4cyl so shifting at 2K rpm was better for fuel economy.
 

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I have an 04 and I drive it hard and get roughly 16.5 mixed between city and highway 50/50. If I loaf it around I get 19-20. I have never gotten below 15 and this was in the winter letting it idle for 10-15 minutes before taking off.
 

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We had an 05 Limited Escape (200HP V6) and we were lucky to see 12 MPG. We average 16 in the GOAT and I drive under varied conditions. Lot of hard take-offs folowed by smooth cruising afterwards.
 

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Discussion Starter #14
I feel a little bit better about 16mpg (I guess:confused ) I will try 2500 rpm shifts and see how that works. How can they say 17mpg city and 25 highway when we have to try so hard just to get 16mpg? oh well I'm not going to loose any sleep over it. :seeya: Thanks
 

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Gas mileage

I get right around 20 mpg on average in my 2004 A-4, in mixed driving. I drive in a lot of traffic at the beginning and end of my 80 mile round trip commute every day. The middle of my commute is through rural areas, where I average around 50 mph. I usually use a relatively light throttle, and run full throttle a few times during each day. My overall average speed is usually in the low 30's. The trip computer mpg has gotten more accurate over time, and usually I am running slightly better than the computer. I have owned my car since 1/22/05 (15 miles on the odometer when purchased), and I now have about 23,500 miles.

By the way, I still have my original stock tires, but I do not like them. They make a lot of road noise, and sound like they are out of round. The car also tends to follow seams in the roadways very badly. Would that be tires or a suspension characteristic? I am thinking of getting Toyo Proxes 4 tires when I have to replace the stock tires. Anyone have any experience with these tires?
 

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My shifts consist of 2k-4k and cruising not in 6th but 5th under 65 mph and then shifting above that.. I run into alot of traffic lights probably 1 every 1/4 mile and farther apart.. I usually run about 300 to 325 miles to a tank.. depending on if I do any racing.. if I do some racing I usually get about 280.. nothing ever lower so far.. and I got 10k on the clock..
 

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dizz81 said:
My shifts consist of 2k-4k and cruising not in 6th but 5th under 65 mph and then shifting above that.. I run into alot of traffic lights probably 1 every 1/4 mile and farther apart.. I usually run about 300 to 325 miles to a tank.. depending on if I do any racing.. if I do some racing I usually get about 280.. nothing ever lower so far.. and I got 10k on the clock..
You have 10k miles already!!!!!!!! How, you have only had that car a few months.
 

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LOL. Sorry, I'm just ROTFLMAO. The first couple months, I got 11.9, or 12.5mpg. I worked my way up to 13.5mpg, and I'm proud of it. If I slow down, I can get 14mpg, but what is the point. They do get better mpg as they break in. After 5,000 miles mine got better. I've got an 04 with 7,200 miles. I'm hoping after 10,000 I'll get 20mpg. LOL..... :lol:
 

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I do about even freeway and city miles, about 400 a week w/ a good amoutn of stop and go traffic as well. I'm getting roughly 18 mpg


I'm doing a road trip soon, I wouldn't be suprised if I saw 25+, i've seen 30+ in my dads vette :willy:
 

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I usually got 16-17 around town. I did the same as GTODealer and would run her up to 2500-2700 to shift. I found by using lower shift points I got worse. I also skipped gears a good bit. 1-3-5 or 2-4-6.
Out on the highway I would get between 23 and 24 with an occasional 25 in there.

Just to make you sick, in the C6 I've been getting about 20-20.5 around town and had one trip to Ft. Lauderdale that I got 28 off of at 78 with the air on. I also had a trip at 82 that got 27.5 and 72 with the air off that got 32.5. The trip computer has always been with-in a tenth of what I get by checking gallons pumped versus miles. Same LS2 just 600 lbs less weight, better aerodynamics and a great 6 speed auto.

Then to make you feel better, the 6cyl Dakota gets 18-19 around town and 18-19 on the highway. Every once in a while I'l see 20.
 
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