bb700092

************* PLEASE READ BEFORE YOU VOTE *************

There have been quite a few MPG threads in this forum and at least one for the 6th gen Maxima (http://forums.maxima.org/showthread.php?t=544386). However, I figured after going through those threads that the MPG of the 07-08 Maxima differ significantly from the other Maximas, even the 04-06 Maximas. Hence this new thread.

While any Maxima owner can chip in with his/her suggestions and tips from experience, I would request only the 07-08 Maxima owners to vote so that the poll results truly reflect the performance of the CVT in terms of MPG.

We all know that many factors influence overall MPG, including % of city/hwy driving, weather conditions, driving habits, and so on. To eliminate some of that, in this poll, we will assume the following:

1. Driving in any roadway with a maximum speed limit of less than 40 mph is city driving. Driving in any roadway with a speed limit of 40 mph or more is highway even though that has signals. Thus, state routes with speed limit 40 mph and signals are considered as highways in this poll. This is assumed because I observe the CVT to provide very good MPG at 40 or 45 mph if the rpm is kept below 2K when accelerating from stop.

2. The overall MPG is calculated by assuming everyone does 50% city driving and 50% highway. But seldom does that happen in reality. So when voting, we would calculate the overall MPG as the average of city MPG and highway MPG. For example, if my city MPG is 15.0 and highway MPG is 22.7, my overall MPG will be (15.0+22.7)/2 = 18.85 rounded to 18.9.

Lastly, I believe, calculating MPG as total miles travelled divided by amount of gas filled is not as accurate as that obtained from the computer. So, hope all numbers would come from the computer.

bb700092

I noticed the following mph and mpg trend in my Maxima during highway driving:

45-60 mph => 28 mpg (I could achieve up to 28.2 mpg once)
60-65 mph => 26.5 mpg
65-70 mph => 25.5 mpg
>70 mph => <25 mpg

In city driving, I get 18-19 mpg. So my overall MPG would be (28.0+18.0)/2 = 23.0.

Currently, I have about 4800 miles on my Maxima and have done my first oil change about a month back. I noticed an increase in overall MPG after the first 2000 miles. I always use 93 octane (if that helps at all) from different brands and gas stations. I drive quite conservatively, seldom going above 1700 rpm when accelerating from stop.

QwikKota

iTrader: (3)

25 Hwy, 20 City. Hopefully those numbers will go up with synthetic oil. I am unsure of why you think the manual method of calculating mileage is inaccurate when that is the tried and tested way. If you drove two complete tanks one in the city other in the highway then you could go by the computer. I have found that if you go about 65 the CVT gets really good mileage but above that it starts to drop off. I usually go 75 on the highway and anything less than 65 you will get run over in Houston. My city would surely go up if I kept it at or under 2k rpm. Hard to not dip into the throttle though.

bb700092

I think the manual method of calculating MPG is not accurate enough not because there is anything wrong with the formula but because one cannot provide exact numbers for the total gas used for the total miles travelled. Most people do it this way: they fill up the tank to the full, then they drive for some, say m miles, and then again fill up the tank to the full, with say g gallons of gas. The MPG then is m/g. Clearly, there is no problem with m. There is a problem with g because a number of factors influence how much gas is actually going in when one fills the tank to the full. Such factors include weather conditions, how hot/cold the car is, whether someone is trying to force more gas in or not, and so on. The computations from the internal computer is free from such factors.

This is how I calculate highway MPG in the computer. Once I get on the highway and set the cruise to a particular speed, I reset the MPG in my computer. Then drive for about 25-30 miles and soon the MPG becomes stagnant. That is my MPG at that speed. I can do that again at a different speed if I want to. In the city, I pick a day on which I would be doing a lot of city driving and no highway driving. At the beginning of the day, I reset the computer before starting my car and then see what my computer says at the end of the day.

I travel mostly on I-95 in FL where the speed limit is 70 mph. I drive at 65 mph to get better MPG. I have sometimes even driven at 60 mph. Even the semis drive at 70-75 mph and pass me quite often. I know that with the power I have, I can leave those semis and many cars a few miles behind in a few seconds if I want to. But right now, I am experimenting with my car's MPG and will not give that up for meagre distractions.

The other thing is I truly consider my car as a luxury sedan rather than a racing car. Every day when I go to work, I feel the nicest thing that happens to me is to be able to drive a beautiful car like my Maxima. The CVT doesn't even let me know when it changes gears. I want to stay in my car for as long as I can and relish the luxury, so don't care if a semi overtook me or a fly flew over my car.

QwikKota

iTrader: (3)

I agree on being thankful for having such a nice car. My 96 was embarrassing to drive but I liked the engine and interior room. I feel it is a great mix of sport and luxury.

If you reset the trip at the pump and record the exact amount of gas that you refill the next time you get gas that is your exact average mpg for the driving you did. I understand your point of getting pure highway mileage. Whether or not the EPA resets their equipment once they reach highway speeds or not I am unsure, but I doubt it. City driving is difficult to get an accurate #, some base it on speed, others on amount of stop and go. I hate the stop part.

Only thing I am curious about is the efficiency of the CVT vs. Automatic vs. 6 Manual. I would hope it would transmit at least as much power if not more than the 5 speed auto or I don't see it as much of a technological breakthrough.

bb700092

I find the CVT's smoothness as the major technological breakthrough. Before I bought my Max, I test drove the Avalon which is bigger but has better MPG at least on paper. The Avalon was very very smooth but still I could feel the gears shifting if I wanted to. In my Maxima, that shifting is just absent which is what I love.

Since the CVT is still in its infancy, I doubt we 07-08 Maxima owners will get as good MPG as the 04-06 Maximas. But with time and more technological breakthroughs, I believe the CVT will provide better MPG than the 5, 6 or even 8-speed Automatics.

I find ample power in my CVT at every speed from 0 to 85 mph. The Avalon that I tried had 268 hp (248 lb-ft torque) 6-speed and when I tried the Maxima, I did not feel any difference in power.

QwikKota

iTrader: (3)

I know the industry standard of luxury cars with regards to transmission is smoothness of shift and lack of hard shifting or jerking but mileage is one of the reasons people purchase Maximas. Blend of performance and economy. I agree the Max's seem to be quicker than similar cars from Honda/Toyota with the same if not more power. Economy is related to gear ratios and efficiency of the drivetrain. A 4 speed auto with the right gear set can return more mpg than an 8 speed etc. If the CVT is set up to mirror the 6 speed's ratio then all it needs to get as good of mileage is the 15% drivetrain loss or whatever it is.

bb700092

You are right that MPG should be of a major concern for all cars including luxury, especially at the current alarming rate of gas price increase. But is it possible to set up the CVT to mirror the 6 (or even 8) speed's ratio?

QwikKota

iTrader: (3)

If each individual manual selection ratio is the same as the conventional 6 speeds and the final drive ratio is the same it should in theory be identical. The efficiency comes into play with torque converter versus clutch. There are some converters that transmit more power than most but the trade off is heat and longevity etc. I just thought it was cool that the CVT had 6 manual selections instead of 5. Another thing to figure out is if there is a 1:1 ratio for dynoing purposes. Rare to not have one in a car of any tranny.

MAXIMIZER08

My friend has an 07 SL and I have an 08 SE other than those two differences they are about the same except his 07 drinks gas and my 08 is averaging about 22MPG.

bb700092

Lol... it would interesting to see what happens if you two guys swap cars for a day

MAXIMIZER08

We have considered that. I think his right foot might be the issue

bb700092

I too think so

DasYears

i get more than 22 in my 02 6spd, you ought to be getting better than that, and if your friend is considerably worse with mileage then it pretty much HAS to be his right foot

zuko

About 21-23 in town. I do no freeway driving and I also don't drive like a pissed off teenager.

bb700092

Hope you guys know about the Gas Guzzler Tax (http://www.epa.gov/fueleconomy/guzzler/420f06042.htm). The combined MPG is calculated based on 55% city driving and 45% highway driving. The combined MPG has to be at least 22.5 to evade this tax.

The published MPG of the 07-08 Maxima is 19/25 city/hwy. That makes the combined MPG = 19*0.55 + 25*0.45 = 21.7 which is less than 22.5.

Do we 07-08 owners had to (in the past) or will have to (in future) pay this tax?

redls1

iTrader: (2)

The tax is initiated when you buy the car. Cant hit you up after. So they got around it somehow.

Strontium

Not sure why you're getting less than 25MPG with highway driving at >70MPH. I avarage 30MPG when doing an average of 80MPH. I squeezed 488 miles out of a tank (to the low fuel light...16 gallons).

Aside, from that, I average 22MPG with mixed highway and city driving. This number is the same both by the onboard computer and calculating it between fillups (for me).

I'm at 15,000 miles. Switched to synthetic oil, at 7,000.

QwikKota

iTrader: (3)

That's crazy how identical cars can vary so much. I usually fill up with mid-grade Texaco and get 25 hwy and 21 or so city. Saturday I got some Shell at one of the cheaper locations in Pasadena and the mileage has not been as good. Drove from La Porte to Galveston and the computer never got much over 22.5. Drove at 75 on the highway with the cruise on for most of it, never letting the engine rev over 2500. I hardly ever drive this way and it seems pointless since I can have much more fun playing with the go pedal and only losing 1 mpg or so. I think that locations gas is discounted for a reason... Will try the experiment again with my tried and tested Texaco station. I put on a Fujita CAI since I've tried to see my best mileage but I don't think it should effect much as long as I'm not testing any power gains.

What part of Houston are you in? Going synthetic very soon.

bb700092

You are getting that mpg in a 07-08 Maxima with CVT? Do you have any mods, special filter, etc.?

I have a little less than 6,000 miles in my 07'max (100% stock). I always use 93 octane gas from different brands. I had only one oil change (due soon for the second) which wasn't synthetic.

I am not very surprised that you are getting better city mpg because city driving is very different for different people. But I am really surprised by your mpg at >70 mph. The best mpg I could ever get by setting on cruise at 70 mph for about 20 miles at a stretch was 26.9 and the same at 75 mph was 25.4. I could hardly achieve more than 25 mpg at speeds more than 75 mph.

Here are some of my mpg's at different speeds. Each of these are averages over at least 5 different observations. Each observation is obtained from the computer by running the car on cruise for at least 20 miles.

MPG @ 50 mph = 31.0
MPG @ 55 mph = 29.5
MPG @ 60 mph = 28.3
MPG @ 65 mph = 27.0
MPG @ 70 mph = 26.0
MPG @ 75 mph = 24.8

Please let me know yours if you have the data.

Also, I would like to know if your mpg increased after a certain number of miles on your odometer. Mine increased a little after 2,000 miles. I now have about 6,000. Can I expect the mpg to increase more after a certain miles?

Anyway, its heartening to hear that a CVT is getting so good mpg. Theoretically, the CVT should get better mpg. Let me just hope mine will also increase with time

QwikKota

iTrader: (3)

Regardless of the transmission on a flat road cruise will get better mileage. I know my foot doesn't like to stay at the same exact setting for very long. Its my experience that unless you are driving at odd hours its almost impossible to be able to use cruise. Too many cars on the road at too many different speeds.

Strontium

No mods. It's an 07 CVT SL. Manufactured in August of 06, I believe.

Can't really provide the detailed data, as you have. I really only pay attention to my gas mileage as an afterthought, anymore. It used to be a big issue, with me, when I was driving an Xterra lol. 16MPG really sucks.

Although, I do miss my Grand AM. That thing got 27MPG mixed city/highway. However, I do not miss the 4 banger.

I, still, cannot believe you are seeing that low of a mileage for 75MPH. How long of a trip was it when you calculated that? My example of getting 30mpg, was while I was driving (nonstop) from Houston to Kentucky. What distance travelled, are you getting that number? That is one of the things that I never liked about the onboard computer. It takes a long time for it to come to actual numbers due to starting and stopping.

Edit: okay, reread your reply. 20 miles really can't be considered a good recording for this purpose. I think, if you drive it at >70 for about a full tank, you will get a different result. So, say a road trip to somewhere. Short distances, I've found, don't really give reliable data. Fortunately, and unfortunately, for me I drive 35mi each way to work. So, at minumum any of my data is based on 35mi trips.

Your mileage is still kind of low, too. However, I don't think you'll see much change between now and say 15,000 miles. Also, a lot of it is going to depend on how you broke the engine in, etc... My car was driven, on their lot, at speeds of around 15mph for the first 900 miles. I think that hurt me, in the end.

I use mid grade octane, for fuel by the way.

Strontium

You know, I used to use Texaco...religously. My habit has changed, over the years, and now I only fill up with Chevron. Pay no attention to the fact that I work in a laboratory in the oil and gas industry. I see what the gasoline that we put in our vehicles looks like...first hand. We sell it to all of the major refineries. In the end, it comes down to the detergent package, and I know for a fact that Chevron's is the best when it comes to this. PS - Stay away from Valero.

Yes, I went synthetic sooner than I wanted. I wanted to wait 'till at least around 15k. However, I feel queasy driving with dino oil. So, I said screw it and did my first OCI at 7.5k and did Mobil One. Car seems to have taken it, very well. Just did my second OCI at 15k. Oil was still very clean, on change. I do my own oil changes as I like to have some form of inspecting my own front end (driving through downtown, you have to inspect your front end a lot).

I live pretty much, right outside of downtown. I'm hoping to change that, soon, however. I used to work in La Porte. Working in Baytown, now, for the past 6yrs.

bb700092

Strontium,
You have the exact same car as I do. You said you receive 30 mpg driving at 80 mph. Can you please let us know what mpg you get at 45-60 mph? Most people I know report better mpg in that range as compared to greater than 70 mph (see http://www.fueleconomy.gov/feg/driveHabits.shtml). So I expect you to get more than 30 mpg in the range 45-60 mph.

QwikKota

iTrader: (3)

Well now that Texaco uses Techron in their mix its pretty much the same huh? I am in oil and gas as well, but on the consulting/contractor side. TEPSCO, LP. Doing piping calcs for Kinder Morgan and Lubrizol etc.

I run synthetics in all our cars but break them in with a blend first. I was not too happy to see Mobil 7500 blend missing from the Autozone shelf this weekend. I have store credit there and went with their conventional for next change, prob do it this weekend. I sell Amsoil so that's what usually goes in and their filters as well. I don't put Valero in anything and the truck usually gets Chevron as well. Gas mileage is pointless to be concerned with in it, lol.

largepkg25

I find it very hard to believe that any max could get 30mpg @ 80mph. Maybe on the rare occasion such as driving with a heavy tailwind or tailgating a semi but certainly not with any consistency.

bb, I'm pretty much spot on with your numbers. Although, if I drive like a blind grandma I have been able to get 25mpg in city driving.

Strontium

Well, you do the math. 480 miles, on 16 gallons.

bb700092

Why are you calculating on 16 gals and not 17, 18, 19 or 20?

04MAX_ILLIN

iTrader: (3)

Not so sure how much MPH affects MPG as RPM's would affect it more i would think. This idea only in my head because I thought that the cvt "doesnt" shift, therefore holding rpm's higher for longer period of time ?

Strontium

When the low fuel light went on, I glanced at the tripometer. If I'm not mistaken, the low fuel light goes on at 16 gallons. Also, I stopped and refilled when the light went on. Refill was 16.1 gallons. I shaved the 0.1 off for distance traveled from the highway, to the gas station a mile down the road.

Strontium

Just a side note. One of my shift-mates, at work, drives an 06 SE. He uses the car for nothing but to-from work (all highway). He uses the computer for his mileage. He swears, up and down, that he gets 29mpg. Obviously, it's not a CVT. I'm not too sure that affects mileage, at this point. Also note, the differences in calculation. He uses the onboard computer. I do not (anymore). I use my car for mixed city/highway. So, I don't often bother calculating my mileage. A couple of times seeing that it is roughly 22mpg with my driving habits/type of driving, I didn't really need to think about it more.

I didn't believe him, either. Until, I drove cross-country and saw that I got 480 miles out of 16 gallons...

All, in all, I'd say 22mpg is not too shabby for a car with 255 horsepower.

bb700092

I don't think the low fuel light always comes on at exactly 16 gals (i.e. with 4 gals of reserve) though it might have happened for you.

Once I was driving home on a highway and my low fuel light came on. I was close to home and was too tired to fill up, so decided to drive home a few miles with the light on. The next morning I drove 6 miles to work and it was all city driving. There was no low fuel light. Then when I was returning back from work, the low fuel light came on again. So between the light going on between the two days, I had driven about 10 miles of which about 7 were city miles. This merely shows that the light does not always go on with the same amount of reserve.

Strontium

This is true, what you describe. If you notice, on an incline, your fuel gauge will be different. I've seen the fuel light come on, while on an incline, then go off after the car levels out.

At the time that I took my reading, the car was level and the light did not go back off. I'm fairly certain of the mileage. However, you are correct in that we have no way of knowing at what exact level of fuel that the light comes on. So, really, I would need to discern the actual amount of fuel left when that light went on. But, by filling up, I got a close approximation of 16 gallons.

largepkg25

Again, I can only speak on my first hand experience and what Nissan calculates the mpg's to be. Nissan (under government requirements) states the Maxima gets 19/25 and these would driving in ideal conditions.

Maybe you have the first hybrid Max...

bb700092

I believe, the 07-08 Maxima has the potential to go over 30 mpg in highways if driven conservatively and the environment is favorable. The reason for my belief is this (http://www.epa.gov/fueleconomy/guzzler/420f06042.pdf):

EPA conducts fuel economy tests in a laboratory on a dynamometer (a device similar to a treadmill). Laboratory conditions can be different from real world conditions for such parameters as vehicle speeds, acceleration rates, driving patterns, ambient temperatures, fuel type, tire pressure, wind resistance, etc. EPA studies indicate that vehicles driven by typical drivers under typical road conditions get approximately 90 percent of the laboratory test-based city mpg value and approximately 78 percent of laboratory highway mpg value. This difference is referred to as “in-use shortfall.” To account for the in-use shortfall, the city and highway mpg values listed in the Fuel Economy Guide and shown on fuel economy labels are multiplied by 0.90 for the city test and 0.78 for the highway test.

Thus, in favorable conditions, the 07-08 Maxima can get 19/0.9=21.1 mpg in the city and 25/0.78=32.0 mpg in the highway. Having said that, I am not sure what speed qualifies as highway speed. If 65-70 mph, which is the speed limit in most highways, is the speed EPA is talking about, then 32.0 mpg in the highway still seems obtainable.

But I still think getting 30 mpg at 80 mph over 480 miles is tough, especially since the mpg begins dropping after 60 mph and it is difficult to find favorable conditions for a stretch as long as 480 miles.

bb700092

It is well known that in 4/5/6 speeds, driving in highways on cruise is more efficient for mpg. Is it more efficient for CVT also? I somehow have the feeling that it is not. But I might be wrong. What do you guys think?

bb700092

Has any of you used Ethos? Here it is: http://www.thegassecret.com/index.ht...756000001Zs1ZZ

Let us know your experience if you have used it or know any one who used it.

wtgkb8

Did a little test today to see what different driving situations effect my 07 Max CVT mileage over 240 miles. For each different scenario...I reset the mpg display just after setting cruise. Here are my results:

Cruise set at 70(speed limit 70) with a 20-25 mph cross wind over 65 miles...mostly flat here in West Central TX: 26.9mpg

Cruise @ 70mph with a head wind of same intensity...and more hilly terrian...ave over 55 miles: 25.6mpg

This one sucked in comparision...

Cruise @ 80(speed limit 80 on I-10) cross wind...few long hill climbs...ave over 55 miles: 22.5mpg!!

And now...the one that really surprised me...

Cruise @ 70...wind at my back...same intensity...a couple small hills...over 65 miles: 31.9mpg!!!!

Filled up afterwards and averaged 26.9 mpg over those 240 miles.

Speed...wind...and terrain all have a significant impact on mileage from these results. Temp was about 65deg...and 5800 miles on the 2007 Maxima SE.

BTW...Earlier this week I had been driving 90% city...and having to defrost the car before driving...with temps in the 20s and 30s...over 65 miles over 5 days...display showed 15.6mpg.

bb700092

Your observations are perfectly in line with mine. Congrats on your 31.9 mpg! I have to try that

cefiro80

Throug manual logging my dad's is getting around 21.56 with mostly city miles.