Y50 M35/45 drivers what are your MPG numbers??

[a.blanco0905]

Ok, so with gas prices going up I was wondering what's the proper MPG for our cars... at different speeds (& conditions if you'd like to share that as well.) I have never been the one to care about gas prices as I ride my motorcycle a lot and I was stationed in Europe and remember their LITER prices, so I cant help but not complain at our prices too much... except for that 08 summer I think it was, I was stationed in Fort Benning, GA and I lived in Phenix City, AL, which was about 20-25 miles to work and gas peaked at $5.35 I believe. I think that premium gas prices are not coming back to low $3 range anymore, so I'm a little more concerned... nonetheless, my freeway avg is 19.9 MPG very steady with minor fluctuations to 20.2 MPG and that's with steady speeds of 75-80 MPH... mostly right at 80 MPH, in the Texas heat... what do you guys average or think about my MPGs?

[FNAWSM]

what about when your computer reads **.*????? I think we have a 20 gallon tank, but maybe 18 or maybe 19.42 or 6. One time i drove a unicorn that was upreved and I got infiniti miles/gallon because he didnt use gasoline, he ran on kisses.

[themacs]

I have an '09 M 35 in CA If I drive easily and constant on the freeway I get 27 MPG. This is hand figured and not by the readout. I must say though, the readout is quite accurate.

In town and freeway 23 MPG ave. Just in town 20 MPG. I have 29K on the car.

[relentless1]

I do 90-95% city driving daily averaging 17mpg. When I drive to LA from San Diego with a little stop and go on the freeway, I average 25mpg.

[EniGmA1987]

I just filled up today. I reset my average speed, average MPG, miles traveled, and distance driven. I will post when I have used this tank of gas to show what I got.


Normally, when I drive how I like, I get 16~ MPG combined city/highway. If I drive easier, I get around 22 MPG. When I drive only highway for the whole tank of gas, I get 27-28 MPG.


Currently, after driving home from filling up tonight (mostly highway, 2 miles of city streets) I have 26.8 MPG. We will see where that goes by the time the whole tank of gas is used.
I am also taking pictures of this for recording it all as proof.




And it is important to note that themacs has a 7 speed transmission while everyone else so far who has posted only has the normal 5 speed transmissions. So thats why his numbers seem so much better.

[The00Dustin]

what about when your computer reads **.*????? I think we have a 20 gallon tank, but maybe 18 or maybe 19.42 or 6. One time i drove a unicorn that was upreved and I got infiniti miles/gallon because he didnt use gasoline, he ran on kisses.

LOL! Don't you mean infinity miles per gallon? Were they eskimo kisses, regular kisses, or french kisses? (ew!) I'll leave it to Antz to ask how you knew it was a he...

[The00Dustin]

And it is important to note that themacs has a 7 speed transmission while everyone else so far who has posted only has the normal 5 speed transmissions. So thats why his numbers seem so much better.

I thought there was a post about gearing once upon a time and the 7 speeds had the same (or very close to the same) final drive ratios as the 5 speeds they replaced. Obviously with the numbers themacs is getting, it sounds like I'm wrong, but do you remember such a thread? Would that have only been true on the 45?

[EniGmA1987]

I thought there was a post about gearing once upon a time and the 7 speeds had the same (or very close to the same) final drive ratios as the 5 speeds they replaced.

The 2009 with 7 speed has a 7th gear ratio of:
Seventh Gear Ratio (:1) 0.77
Final Drive Axle Ratio (:1) 3.35

Whereas the 2006 (non-AWD) is:
Fifth Gear Ratio (:1): 0.84
Final Drive Axle Ratio (:1): 3.54

2006 (AWD):
Fifth Gear Ratio (:1): 0.84
Final Drive Axle Ratio (:1): 3.69

[FNAWSM]

what about when your computer reads **.*????? I think we have a 20 gallon tank, but maybe 18 or maybe 19.42 or 6. One time i drove a unicorn that was upreved and I got infiniti miles/gallon because he didnt use gasoline, he ran on kisses.

LOL! Don't you mean infinity miles per gallon? Were they eskimo kisses, regular kisses, or french kisses? (ew!) I'll leave it to Antz to ask how you knew it was a he...

They were hershey kisses and I know it was a he because the nametag on his shirt said Bruce. I only posted my original comment because Blanco already started this exact same thread but it was highjacked by gas tank talk and therefore renamed and this thread was born. I was jokingly taking this one in that same direction, glad to see no one else followed. lol Have a good day everyone!

[crazyjkz]

I thought there was a post about gearing once upon a time and the 7 speeds had the same (or very close to the same) final drive ratios as the 5 speeds they replaced.

The 2009 with 7 speed has a 7th gear ratio of:
Seventh Gear Ratio (:1) 0.77
Final Drive Axle Ratio (:1) 3.35

Whereas the 2006 (non-AWD) is:
Fifth Gear Ratio (:1): 0.84
Final Drive Axle Ratio (:1): 3.54

2006 (AWD):
Fifth Gear Ratio (:1): 0.84
Final Drive Axle Ratio (:1): 3.69

It's interesting to see that there's not THAT much of a difference in the top-gear ratios and final drive ratios between the 7-speed auto and the 5-speed auto. I figured their would of been a bigger difference since the 7-speed seems to be geared for primarily fuel economy over performance which is why the 7-speed models are supposed to be about the same in 0-60 and 1/4 mile times when compared to the older 5-speed models in the 2008 G37 and 2009 G37 (I used the G37 as an example because all other factors were equal except for the transmissions).

I definitely do understand why Infiniti used a 3.54 and 3.69 final-drive ratio for the M35 and M35x, this is clearly a performance-luxury sports sedan that is geared for sporty/aggressive driving over merely soft cushy luxury and fuel economy, but I just don't understand why they had to use such a short 0.84 5th gear ratio. They could of kept the aggressive final-drive ratios the same while just simply making the 5th gear ratio a little taller since it's the overdrive gear anyway, something like maybe 0.75, and it would of lowered the highway rpms down some which would ultimately make 5th a more suitable overdrive gear which would increase highway fuel economy and lower engine/exhaust noise at highway speeds with a very minimal loss in acceleration and performance, especially considering that 5th gear isn't really used for high acceleration anyway.

Overdrive should be a REAL overdrive gear ratio, especially when you have less than 6 gears in your transmission. The overdrive gear is supposed to be designed for maximum highway fuel economy and reduced engine/exhaust noise at highway speeds as opposed to high acceleration and performance, therefore it doesn't need to be a short and aggressive gear ratio because in the 5-speed auto you have 4 other well-spaced gear ratios for good acceleration and overall performance to get you up to the higher speeds, but the overdrive top-gear ratio of a transmission should be a little taller so that you get the most fuel economy possible on the highway and the lowest engine/exhaust noise to make a comfortable and relaxed highway ride.

Although I'm not really complaining about it, I do love my M35x, and the highway rpms aren't really that high especially compared to some other sporty performance cars out there, I'm around 2500rpms or so at 65 mph which is a standard highway cruising speed in the area I live in NY, and actually I think the Jatco RE5R05A 5-speed auto in this car is probably one of the best 5-speed automatics that was ever made and it was definitely ahead of it's time in design and technology, and I also do think that 1st, 2nd, 3rd, and 4th gear ratios are VERY well-spaced with an overall very good power/acceleration spread, but I just think that if they had used an overdrive gear ratio of around 0.75 for 5th gear it would have helped with overally highway fuel economy without really sacrificing the powerful and sporty acceleration and performance that these cars are well-known for. Just my two cents.

[a.blanco0905]

I have an '09 M 35 in CA If I drive easily and constant on the freeway I get 27 MPG.

When I drive to LA from San Diego with a little stop and go on the freeway, I average 25mpg.

city/highway. If I drive easier, I get around 22 MPG. When I drive only highway for the whole tank of gas, I get 27-28 MPG.

These are astonishing numbers to me... but then again if I could drive 55 MPH constant I could probably get way better MPGs on my M45 than 19.9 at 80 MPH. You guys never mentioned how fast you were going, just "easy" or "hard" tho...

[EniGmA1987]

65 mph on freeway for easy, 75-80 mph driving normal. For me anyway

[Em35X]

I get less than 20, at least according to the car. This is highly annoying because most of the miles are highway and parkway. I was once able to get up to 23 by using cruise-control to an extent that would reasonably be called unsafe, lol.

It's always been this way. When I got the car with 12k miles on it, it was doing less than 20. Today it's still doing less than 20 (again, according to the car).

I pay about $4.40 a gallon here in Potomac, MD, by the way and drive 45 miles a day to work and back (accumulatively).

Needless to say, it blows (the amount I spend on gas, that is).

I should note that I do use auto-manual quite a bit but even when I was on full auto it didn't make much of a difference.

[EniGmA1987]

The trick is to get up to speed somewhat quickly. If the speed limit is 40mph, get up to 32mph somewhat quickly (not flooring it) and then slowly get up to 40 after that. The rise from 32 to 40 is doable and while you are slowly accelerating still, you are getting 22-23 mpg. Once at 40 you are cruising at 28-30 mpg. Any speed less than 32 mph just get up to speed quickly and cruise there. If it is more than 40 mph speed limit then do the same thing but probably get up to a higher speed relative to the streets speed limit before you start the slower acceleration.

[a.blanco0905]

I have the same driving habits enigma, and EM you have an AWD so that's dragging your MPG down even if it's a 35... that's more or less what Ilyakol gets for MPGs too. As far as doing all that to save on gas, err, too much for me... I'm actually driving like a model citizen (on this gas tank... as an experiment) to see how many miles I'll get to my tank, after I put 17.80 gallons... so far I've traveled 65 miles and I'm one thick mark above 3 quarters...

On a 2011 elantra 65 miles would've been a little over 1 1/2 gallon of fuel and a little over $7 (cheap gas) on my M it cost me almost $17.50 lol...

[relentless1]

When I drive to LA from San Diego with a little stop and go on the freeway, I average 25mpg.

These are astonishing numbers to me... but then again if I could drive 55 MPH constant I could probably get way better MPGs on my M45 than 19.9 at 80 MPH. You guys never mentioned how fast you were going, just "easy" or "hard" tho...

For 80% of my trip I go 80mph. The other 20% (when im in the LA area) I go 65mph.

[crazyjkz]

The trick is to get up to speed somewhat quickly. If the speed limit is 40mph, get up to 32mph somewhat quickly (not flooring it) and then slowly get up to 40 after that. The rise from 32 to 40 is doable and while you are slowly accelerating still, you are getting 22-23 mpg. Once at 40 you are cruising at 28-30 mpg. Any speed less than 32 mph just get up to speed quickly and cruise there. If it is more than 40 mph speed limit then do the same thing but probably get up to a higher speed relative to the streets speed limit before you start the slower acceleration.

I eventually learned this trick as well over time. At first I thought that it would be better to just keep the rpms down as much as possible with a somewhat light throttle even when getting up to a normal around-town cruising speed of about 40mph or so, but I soon learned that it actually seems to hurts the gas mileage if I do that. It's better off just getting up to the road's cruising speed limit relatively quickly rather than dragging it along with very light throttle and low rpms because once you get up to say a 40mph steady cruising speed you will be getting some of the best gas mileage possible because you will be below 2000 rpms and the torque converter should be locking up at this point for low rpms and therefore maximum fuel economy.

With a moderate foot in my 2007 M35x I manage to average around 18 mpg or so in normal around-town driving and on the highway at a 65-70 mph steady cruising speed I average around 25 mpg or so. This is based on the computer mpg read-out, and I always reset it whenever I change from city to highway driving and vice-versa. I just got my M35x a few weeks ago and this is definitely better gas mileage than I had expected with this car especially since the EPA numbers are only 16 city/22 highway which sounds pretty bad, but nevertheless I seem to get better real-world mileage than these EPA numbers suggest.

I added a bottle of Chevron Techron fuel-system cleaner a few days ago and that seemed to give a minor improvement in overall fuel economy, plus a few days after I got the car I put on 4 new Kumho LX Platinum tires and I keep them at around 37-38 psi which also seemed to help the mileage a bit when compared to the worn out OEM tires that were on the car when I first got it. Oil and filter change, air filter, and drive belts were all done at the Infiniti dealership before I picked the car up. This weeked I'm having the dealership do a complete transmission fluid flush with Nissan Matic S and they are also changing the differential and transfer fluids as well. Proper maintenance, a clean fuel system, good driving habits, and solid tires with the proper inflation definitely seems to help get the most out of each gallon of gas.

[EniGmA1987]

Ive had these pics sitting on my desktop for a while now, so Im finally getting around to posting this. This was the best MPG I could get for a tank of gas. I filled up completely and drove until the gas gauge said I was just a bit above the E, strangely the "time for a fill up" light never came on... I looked really low, lower than I normally go between fill-ups. And yet I hadnt even used 16 gallons. So IDK. Whatever. MPG is still MPG no matter how many gallons you have used. On to the pics!




I filled up completely to start (obviously). My MPG after my drive home from the gas station, this was a little less than 26 miles of driving on the tank of gas so far:




Now after a few days, here I am at a half tank: Beautiful picture huh? I took these on my phone. Crazy.




A day or two later, getting a bit lower. This time I took a picture of the gas I have left, and of the MPG screen at this same time:





^^^^^
Kinda low MPG it says on that screen. IDK. I guess the computer MPG screen isnt always the most accurate.



Here I am at the miles drive and amount of gas left in the tank at the time I filled up: Notice no light telling me to fill up. Odd.



And the MPG screen at the time right before I filled up. This is taken right after the previous picture:




These next ones need a bit of explaining, this picture here is how much I filled up until the pump auto shut off:



Then I pumped a tiny bit more just to make sure the tank was full. I did this because with where the gas gauge said my fuel was, 15 and a half gallons just didnt seem like it was enough to fill up the tank. But sure enough, after trying to pump more, the pump auto shut off again. I took this next picture to show that the gas tank really was very full and started spilling out after I kept trying to put more gas in after it had already automatically shut off the pump:




here is my receipt as proof of how much was pumped and paid: notice the time in these pictures, and how much was pumped. Again, the slight discrepency in how much was pumped is because the last pic was after the auto shut off, this one is the total pumped after I kept trying to put more in the gas tank



And a pic right after I got back in the car from filling up, showing the tank is full and the miles I had driven on the last tank of gas:






EDIT: lol! I forgot to tell you the math for all this! ok so:
357.6 miles traveled on a single tank of gas
15.572 gallons of gas were used to travel that distance.

This equates to:
22.964 mpg combined city/highway


Technically, the pump shut off at 15.343 gallons, so I have slightly better MPG. But I did these calculations based on what the receipt said after I kept trying to fill up the tank more.







And this next shot is after driving home from the gas station. This driving distance was almost all freeway, just under 24 miles of driving:

[EniGmA1987]

And yes, that receipt is of Arco gas, 87 octane. As I have said on these forums in the past, I get the same MPG with Arco gas as I do with Chevron, and the worst MPG with Shell. I also found absolutely no power difference between 91 and 87 octane. The engine does not ping at 87 either, the only time I have had pinging at all is when I use Shell gas. And for all of you about to go on a crazy "OMG you must use premium gas" rampage, no I do not have to. YOU do, but my manual says I can use anything. However, premium is just recommended. It also says on the gas tank cover that 91 is only what is recommended, not required.

Besides, how can you argue with 31 mpg on the highway with 87 octane gas? Obviously something is working right.


Oh and also, this was done when I was in need of an oil change, a bit overdue actually. My spark plugs are also overdue to be changed. And I need an alignment Wow I need to keep up on maintenance more...
And tire pressure was set at 33 PSI cold.

[jayfox911]

highway SD to Vegas last weekend @ 70-80 MPH, I got 23.1 MPG
Mixed driving to work (15 mile commute), I get 18.5

Stock sport rims (8.5 inches wide) with bridgestones tires 245/40-19, PSI 35

When I had 20 inch rims (9.5 front and 10 rear wide), I was getting 16-17 mixed and 21 highway

[a.blanco0905]

^Great post Enigma... I wish I had your balls and put 87 oct on my car (and especially on the wife's truck) but I really dont want to risk anything over a few dollars, u know. This kinda makes me want to sell my 45 and get a 35 but before I'd even do that I would have to drive an M35 and see if it's a big difference. I might just wait a couple of years and get a hybrid as I've planned all along and just suck it up... btw I'm averaging 16.2 a tank on 95% city driving & 5% hwy, no seriously where I live is a very small place.

[EniGmA1987]

16.2 for almost all city driving on an M45 really isnt so bad IMO.

[a.blanco0905]

16.2 for almost all city driving on an M45 really isnt so bad IMO.

Ya, I feel it's not too bad considering that I used to get 14. something and even 13.9 when I first got it... and I've tried to baby it but I just cant.

[sunoco]

And yes, that receipt is of Arco gas, 87 octane.

Arco is owned by BP, man!! I would def. buy from Chevron if you get same mpg. BP is the devil. To bad there are no Sunoco stations on the left coast.

I have a 2007 M35 and the highest my fuel economy calc on the car has shown is 24.2.

[mexillis]

I just went to NC and averaged about 23 MPG and thats with 75-80 for the majority of the way and I had a couple times of >100 and a cruising speed of >80 for a long period of time. My light came on around 360 miles on the trip computer. I dont have any pictures but at 3/4's of a tank I had about 109 miles at half it was around 220 and then 340 at 1/4 tank left then entered the city. I use shell most of the time, figured I'd throw that out there since some have mentioned it above.

[a.blanco0905]

^That's pretty good... I get around 20-21 MPG at 80 mph & ocassionally a little faster on trips to San Antonio & Houston...

I mean... I get 24 MPG in the City & 37 MPH highway. Lmao...

[mexillis]

http://files.sharenator.com/funny_pictu ... 58-580.jpg

[VincentG37]

I guess my M45 has the best MPG which is 99.9MPG.

[The00Dustin]

I guess my M45 has the best MPG which is 99.9MPG.

Wow! So when took that picture was taken, you had already gone roughly 1525 miles on that tank?! Impressive.

[ncm35s]

Thought I'd share my results since I just did a long trip in my 35 and had similiar results as Mexillis. I averaged 23.5mpg on a trip last week covering over 500 miles. The trip computer had me an average speed of 74.5mph. Most of the time I was set around 80mph but did have some short stretches going over 90+. Had another trip with avg speed of 68mph and returned 25.6mpg. I use Shell mid-grade octane (not sure why, guess because I feel guilty if I used 87 octane but don't want to pay for the 93 octane). I have 34k on the car.

Also, I agree on the acceleration; it seems that coming up slowly to speed actually hurts vs. getting up to speed quickly. Thought it was a fluke until reading in thread that others seem to have similiar results.