Mazda5 real-world Mileage numbers

I don't know about you, but when I rent a car, I put as little fuel as I can into the tank when returning it to the agency. Just has to appear to have a full tank. I definately do not squeeze absolutely every possible drop of fuel into that tank. I bet you could put at least three more galllons into the tank of my returned rental car. Never been called on it, nor charged extra on my credit card (so far).
 
No, I won't have accurate numbers. I know how to check MPG (using the odometer) and have a degree in math and in engineering. I check the mileage on every vehicle I own and have for over 20 years now. This car is different than all others.....I'm not the only person who feels that way because every owner i've ever talked to in person confirmed the same. I just say it gets about 25 MPG and call it done now.
For someone who claims to have a degree in math and engineering, and has tracked mileage for over 20 years, I find it odd you don't seem to understand averages.

No matter how wacky pen-and-paper mileage readings may be on a single tank (and they're NOT in my case), over a period of time and multiple top-offs you will get a very accurate sense of what your vehicle is capable of. The shape of the fuel filler neck or the tank, the slope of the spot where you fill up on a given day, short fills, whatever... If you start with a tank that is basically full, track your mileage and fuel top-offs over a period of multiple tankfuls, end with a tank that is basically full, and in the end you will have as accurate a representation of your mileage as can possibly achieve within the obvious limitations of not knowing if the pumps you've used are perfectly calibrated (and, of course, the accuracy of your odometer). You started with a full tank, you ended with a full tank, and the only variability is a gallon or two at most from start to end, depending upon where you stopped adding fuel at the beginning and the end... Use 20 or more tanks and that introduces a very, very small error. Even if you only added 1 gallon 250 times, you still used more or less exactly the same amount of fuel in your driving as in the case of 20 12.5gal fillups (of course more frequent fillups insert more errors, but those errors are minimal too).

You claim to have all these experiences with fuel spilling all over the place. I don't know if it's the pumps where you live, but I've had a little seep maybe one fillup in ten. Total of all those overflows? I dunno... Maybe half a pint? Probably less? In your case I don't know but it's doubtful it's more than a few ounces at a time, if even that much, unless there's something very, very wrong. A little gas can look like an awful lot when it's dripping down your fender flare... And what's even FIVE oz. (aka- A LOT of spillage) compared to a 12gal fillup? About 1/3 of 1%. Hardly enough to throw your whole mileage spreadsheet into a tailspin. Your 25mpg average becomes... 24.92mpg. Again, statistically insignificant, and that assumes you spill nearly half a soda can's worth of gas on EVERY fillup.

Why people bother posting single-tank numbers is a mystery to me... Especially if, as in the case of the person above who rented a 5, you are using such a small amount of fuel as the basis of your calculation, possibly inserting a HUGE error in your calculation. Individual tanks are highly variable based upon the level of the last fillup vs. the level of your most recent fillup, so you need a much larger sample to get an accurate reading.

If you're so inclined, you may even throw out a portion of your highest and lowest readings as representative of the variability in individual fuel pumps (almost never 100% accurate), uncharacteristic driving styles on individual tanks (such as absolutely ALL highway or ALL in-town on a tank), weather (very hot, very cold, raining, snow), traffic or extended idling, overfills or short fills, sunspots or whatever else you can think of. Let's just say drop the top and bottom 10% and figure it from there, if such a thing makes you happy.

In any case, Robotaz, your assertion that you just default to "it gets 25mpg" is pretty close to my experience. I don't have my most recent numbers in front of me, but over the first 10k miles on my 5 (ending this past February) I've gotten a near-enough-as-makes-no-difference average of 24mpg without throwing out any unusually high or low individual numbers, using a sample of 34 fillups.

Edit: Mine is an '09 Sport with a MT
 
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In any case, Robotaz, your assertion that you just default to "it gets 25mpg" is pretty close to my experience. I don't have my most recent numbers in front of me, but over the first 10k miles on my 5 (ending this past February) I've gotten a near-enough-as-makes-no-difference average of 24mpg without throwing out any unusually high or low individual numbers, using a sample of 34 fillups.

Edit: Mine is an '09 Sport with a MT
I'm right there with ya. I don't check every tank (I think I mentioned that earlier) but I DO know that when I get to about 300 miles on a tank, it takes around 12 gal to fill it up again, little more, little less. it's mixed driving, so I'm cool with that.
robotaz for some reason wants to be all negative about the supposed design of the tank and filler neck that no one else has experienced. really don't know how you can have a spill with automatic shut off pumps. I haven't had a spill maybe once in 25 years.
 
I haven't had a spill maybe once in 25 years.
Funny you should mention that. I had a spill less than a month ago. There's been at least two other times since I've owned this car where a significant amount of fuel has slipped up the filler pipe and wetted the area around the fuel intake. Not enough to classify as a spill but enough to note. All three "incidents" were at different filling stations as well.
I've been recording my fill-ups on Ecomodder. Based on what I've recorded there I'd agree with the idea that the 5 is pretty sensitive to temperature changes. With summer temps here I'm getting 28+ MPG out of 60/40 city/hwy. During last winter I went as low as 22 MPG but I think that was increased by lots of stop-and-go traffic that week.
 
I don't know about you, but when I rent a car, I put as little fuel as I can into the tank when returning it to the agency. Just has to appear to have a full tank. I definately do not squeeze absolutely every possible drop of fuel into that tank. I bet you could put at least three more galllons into the tank of my returned rental car. Never been called on it, nor charged extra on my credit card (so far).
That's what the smart man/woman would do. UNLESS, you are 100%compensated for your gas, therefore, to avoid potentially missing a flight, you'd overfill the tank at a station before the airport with less people so you don't have to mess with the poo poo station right before or at the airport :D
 
I get you. I once drove from downtown Hamilton, Ont to the airport with a light fill-up and dropped off the car with the guage still showing full (25 km, I think). I pity the next renter, who probably saw the guage drop to 3/4 of a tank as they drove out of the lot :0
 
Man I forgot to report my great triumph. I drove 357.3 miles and consumed 10.2 US gallons of fuel doing so.

357.3/10.2 = 35.03mpg.

Trip was flat for most of the time. Very little wind. Speeds were around 60mph most of the time, with some stretches at speeds lower than that.

Dudes over at OdyClub are doing all sorts of things to get 25 hwy mpgs. Hahahaha.
 
Man I forgot to report my great triumph. I drove 357.3 miles and consumed 10.2 US gallons of fuel doing so.

357.3/10.2 = 35.03mpg.

Trip was flat for most of the time. Very little wind. Speeds were around 60mph most of the time, with some stretches at speeds lower than that.

Dudes over at OdyClub are doing all sorts of things to get 25 hwy mpgs. Hahahaha.

Let me guess, you've only filled it up a few times? I got 37 MPG once, LOL. Then I got 19 in the same conditions. Wonder why.
 
...Why people bother posting single-tank numbers is a mystery to me...
Reminds me of people on a different forum I belong to (for Hondas) who use the number of miles between fillups as their only method of determining gas mileage. They don't even look at the number of gallons they put in the tank, only how many miles they go between fillups. Weird.

Anyway, Robotaz, do you have vapor recovery pumps where you live? That would be the only reason I can think of for your issues with the gas tank. I have never had gas seep out on my Mazda5, the pump always shuts off automatically when the tank is full. OK, it has seeped once or twice, but only when I tried to "top off the tank", I figured out pretty quickly that when the pump shuts off the tank really is full on the Mazda5. We don't have the vapor recovery pumps here.
 
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I'm getting about 24.5 on mixed driving, with a high of 28+ and low of 22.4. Then again, living in Phoenix with high heat isnt helping me much too.
 
There are too many variables that affect individual MPG calc to get a good comparison. Things such as unsprung weight (wheel and suspension), tire pressure, air temp, heavy/light foot, city vs country vs highway, constant speed vs variable, auto vs manual (gearing and coasting), elevation, headwind vs tailwind, junk in your trunk (both you and the car), etc.

I would recommend everyone to take a few minutes post their numbers on www.fueleconomy.gov (no relations obviously as it is a .gov). This will allow you to see others in your general area along with general driving condition. Also benefits the greater good of the interweb.
 
There are too many variables that affect individual MPG calc to get a good comparison. Things such as unsprung weight (wheel and suspension), tire pressure, air temp, heavy/light foot, city vs country vs highway, constant speed vs variable, auto vs manual (gearing and coasting), elevation, headwind vs tailwind, junk in your trunk (both you and the car), etc.

I would recommend everyone to take a few minutes post their numbers on www.fueleconomy.gov (no relations obviously as it is a .gov). This will allow you to see others in your general area along with general driving condition. Also benefits the greater good of the interweb.

That's very good advice for those seeking to get an impression of real-world mileage figures, and to see how they stack up to their own numbers (which is the object of this thread). But I always kind of think that these threads end up taking the turn of "who can get the best mileage from their car and brag about it?" -which is exactly what I've done with my last post here. :-).

Still, the info is not completely useless as it can turn into a bit of a competition and help people aspire to higher MPG numbers all around.
 
Click on sig below \/

Sign up for Fuelly, guys. There's only 38 of us and I'm the only one with a 2010. You can set it for miles/kms and Gal/L for US-Canada.
 
Just signed up for the Fuelly thing. 36 fill ups, 22 mpg average, high 28, low (OMG), and I want it to be a better ave, but small town and 5 minute commute.

A reasonable tradeoff, I suppose :)
 
Cool, just click on the Fuelly badge located at the bottom of your profile screen and copy and paste and then everybody can see your real-world millage.
 
One thousandkm over 2-500km trips. Got 28 mpg (7.9L/100km) average while flogging the hell out of the 5. Wahoo!
 
took a weekend trip for the 4th, 99% interstate driving and got 27.6 mpg from our 09 Mz5, completely stock, AC on the entire time, did the speed limit majority of the time. Not bad, not as good as my Mz3, but not bad at all imo.
 
just did a 3000+km round trip of Quebec and PEI and averaged 8l/100km (29.4 mpg) that's with the car fully loaded and a bike hanging off the back on a hitch mount rack!

not bad considering we had a full car (2 adults, 2 kids and all their associated gear!)
 

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