Mile Per Gallon!!!!

3.5l mpg vs 3.7l mpg

My wife has owned both CX-9s with the 07 GT and 2010 Touring, both FWD. We have taken both on the same route on our family vacations from the coast of Charleston,SC to Nashville,TN. 1600 miles round trip. The 07 GT got between 25 - 28mpg of mostly highway driving at 75 -80 mph avg. and even got 29 mpg on a tankful (460mi. on 16 gallons). This is with 5 people on board with a Thule roof top carrier.

With 7000 miles on the 2010 Touring, we have yet to reach 22 mpg on the highway with only 4 people carrying the same roof top carrier. Driving at 70MPH with other cars constantly passing us, we only got 324mi. using 15 gal. of fuel, that's only 21.5 mpg. And folks, you'd be hard pressed to notice any performance gain with the 3.7L engine. Why did Mazda feel the need to put the larger engine in the CX-9, thus making the gas mileage much worse?

City driving also suffers with the larger engine. The 07 GT got 17 -18 in city but the 2010 Touring only gets 15-16 on the same commute to work.

Don't get me wrong, we love the CX-9 but not happy with worse gas mileage. Heck, the Honda Odyssey we traded in for the Mazda always got 25 - 30 mpg on road trips and that thing weighs 200 lbs more than the Mazda and a much larger drag coefficient. (yupnope)

My VW Touareg V8 with full time AWD weighing in at a whopping 5200 lbs.(350 HP and 8000 lb towing capacity) gets 15 mpg in town. What gives?
 
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Sad to say that your 2010 sounds similar to my 2008 AWD GT.
Highway: 21-23mpg. Local: 15-17mpg. Mixed: 17-18mpg.
Remember that the '07 has 3.5L engine.
Being a FWD, your 2010 seems to be too thirty. Check the tire pressure.
Are both 2007 and 2010 running the same PSI?
 
Sad to say that your 2010 sounds similar to my 2008 AWD GT.
Highway: 21-23mpg. Local: 15-17mpg. Mixed: 17-18mpg.
Remember that the '07 has 3.5L engine.
Being a FWD, your 2010 seems to be too thirty. Check the tire pressure.
Are both 2007 and 2010 running the same PSI?

Yes, being an engineer, I make sure that tire pressures are correct and the same as the 07. Actually, I put 3 psi more than what the door panel sticker calls for. It helps make sure of even tire wear and the perceived better gas mileage. If you read my post, I was asking why they went bigger with the engine and thus worse mileage than the 07 with no noticeable performance gain.
 
23mpg on this weekends trip up to washington, full of gear and dogs and including some serious hills and windy roads. i'm happy with it!

Al
 
I'm down to 12 mpg now nearly every fill up.
I can never get more than around 240 miles before empty.
:-(
Sadly this is with mixed driving too, not just light to light.
But hey, I never complain about it until I get an email that someone else is getting 23 mpg! Then I complain for a minute and quickly forget. It is still a good car, 23 or 12 mpg.
 
I'm down to 12 mpg now nearly every fill up.
I can never get more than around 240 miles before empty.
:-(
Sadly this is with mixed driving too, not just light to light.
But hey, I never complain about it until I get an email that someone else is getting 23 mpg! Then I complain for a minute and quickly forget. It is still a good car, 23 or 12 mpg.

Hey guys, would this have anything to do with the ethanol that's in most gasolines now? Its getting harder and harder to find gas w/out ethanol in it.

I know ethanol is really bad for engines, performance and reliability wise.
 
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I think gas formulation has quite a bit to do with it, and it's not just ethanol. Certain cities have special requirements other than ethanol for pollution control, so the gas manufacturers are required to change formulation in the summer months. That special requirement is part of the reason why gas goes up, because it's more expensive to manufacture. Whether that has an impact on mileage, I don't know, but I would imagine it has some impact on mileage/performance.
 
I think gas formulation has quite a bit to do with it, and it's not just ethanol. Certain cities have special requirements other than ethanol for pollution control, so the gas manufacturers are required to change formulation in the summer months. That special requirement is part of the reason why gas goes up, because it's more expensive to manufacture. Whether that has an impact on mileage, I don't know, but I would imagine it has some impact on mileage/performance.

I am not the everyday driver of our 9, but I know for a fact my 2000 Tundra gets 1 1/2 to 2 1/2 mpg less in the winter than in the summer. I, out of habit, figure and record my mileage at every fill up.
 
I was driving in the U.P. of Michigan and upper Wisconsin a couple weeks ago. My 2010 had about 2k miles at the time. I was able to go 409 miles on 17.6 gallons which equals just over 23mpg.

I attribute these numbers to a massive amount of road construction forcing me to keep the car at around 60mph most of the time on the expressway.

Incredibly frustrating but apparently a good way to get the best mileage. I would add there were a handfull of WOT passes included in this figure so I could have done even better.

In town driving only mileage has not been checked yet, but I plan to do it soon and report.
 
I was driving in the U.P. of Michigan and upper Wisconsin a couple weeks ago. My 2010 had about 2k miles at the time. I was able to go 409 miles on 17.6 gallons which equals just over 23mpg.

Just got back from our summer vacation. Drove a total 1640 miles from east coast of SC to western part of Tn in our 2010. Average speed of 70 - 75mph. 6 people in the car and a Thule cargo carrier on top (same setup I had on my 07 GT. The best tank was 367 miles and filled up with 17 gallons. That's a little over 21.5mpg. Not very good considering the 07 GT got 25mpg and a best of 28mpg on the same trip.

I just can't figure out that going from a 3.5l to the 3.7l engine affected fuel mileage this much. The performance is not even noticeable between the two engines. I should have kept the 07. (notcool)
 
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I have come to realize that my CX-9 gets better MPG with Chevron than Shell.

I have used nothing but Chevron in my vehicles for the last 5 years, and almost always at the same station.

My CX-9 would typically read 200 on the trip meter when reading 1/2 tank on fuel gauge. I normally fill up at 1/2 tank.

Many of the Chevrons in my area went out of business with no notice a few months ago, forcing me to switch to Shell. I was getting about 170 miles out of 1/2 a tank with Shell.

My favorite Chevron opened again, and I am back to about 200 miles on 1/2 tank.
 
Gas Mileage

I have a 2010 CX-9 Touring with about 3500 miles on it. Here is what i get for mileage. On short trips from my house I get about 15 mpg. On trips to work, which is 1/2 city 1/2 highway I get about 18. On highway travel with cruise at 65 I got 24.5. Driving 75 with A/C on I got 21.5. So basically short trips kill the gas mileage. BTW I use regular gas.
 
Mileage 2010 Sport

I just made a quick haul to Fort Worth and back at speeds ranging from 65-75, and we got 23.5. I get about 15.3 in town - but could do better if I chose to do so. I have 4025 miles on the vehicle. I try to stay on cruise control, can't beat it for metering. I like it just fine, I came from a 10-12mpg Expedition!
 
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i just traded in my 2008 Mazda5 for 2008 CX-9 Touring. I get about 14-15 in town, most in fairly heavy traffic. Can't complain, was expecting worse.
 
i just traded in my 2008 Mazda5 for 2008 CX-9 Touring. I get about 14-15 in town, most in fairly heavy traffic. Can't complain, was expecting worse.

Oh yes you can complain!
Seems sometimes that's all this forum is for unfortunately.

Personally the mileage is not all that important to me because if it was, I would have bought a different vehicle. Crossovers are about mixing aspects of different vehicles, sort of like all season tires. Compromises are made everywhere. They're pretty good at many things but not as good as some specifically designed for a particular task.

I will admit a hybrid CX-9 would probably be a good move for Mazda but that's not what Mazda is about in my opinion.
 
i just traded in my 2008 Mazda5 for 2008 CX-9 Touring. I get about 14-15 in town, most in fairly heavy traffic. Can't complain, was expecting worse.

I also traded my 2006 Mazda5 for a 2007 CX9 FWD Touring, but I get about 16-17 in city driving. I love everything about my CX9, but I do miss my little Mazda5 from time to time.
 
My 2008 CX9 AWD traveled from the Chicago area to Denver this summer and got 23 - 25 MPG. All highway driving using cruise control set at speed limits of 70 - 75 mph. Around town it gets 19 - 20 mpg. Overall we are very pleased with its performance.
 
Our 2008 AWD CX-9 *might* be able to squeeze 23 mpg on the highway on road trips, fully loaded with 2 kids and luggage. But the last trip it barely got 22 mpg. Around town dips down into the 18 range, with 16 being the norm in the winter (and for us, around town means a mix of hwy and traffic).

I hear the new Odyssey minivan, which itself is a heavy pig, will get up to 28 mpg, and that's with their 3.5L engine. So obviously there is a way to squeeze more mpg, not sure how Honda is doing it.
 
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