Silvermax; I will try mine tomorrow and see. I do know my 5 speed auto RPM's were just under 2000 RPM at 60 and I believe my 6 speed is at around 2200 RPM. Maybe that is why the gas mileage is 1MPH more on the auto. The lower the RPM's the better the gas mileage when you are cruising at highway speed. The people without stock size tires may get a slightly different reading.

 

The two points I know on a graph of engine speed vs highway speed in 6th gear are at 2 K RMP the Max is going 55 MPH and at 3 K RPM it is going 83 MPH.

I agree with you that if the Max was geared differently (so that engine RPMs were lower at highway cruising speed) it would get slightly better highway gas mileage. I would prefer that 2 K RPM were closer to 62 MPH (also 100 KPH). But the Nissan engineers gave us a close ratio 6-speed that is more suited for the track than the interstate. Also, it is geared so that when you are passing someone going 55 MPH, you can pass without having to downshift to a lower gear.

The close ratio 6-speed is great at the track for keeping engine RPMs in the max horsepower range. But a wider ratio 6-speed manual trannie would give us a somewhat lower 1st gear for starting and a higher ratio 6th gear for highway cruising. If I were choosing the gear ratios for this 6-speed trannie, I would leave 3rd gear alone and then lower the ratios slightly on 1st and 2nd gear. I would raise the ratios slightly on 4th, 5th, & 6th gears. This would accomplish what I think the Maxima needs to be a better highway cruiser. But the trannie would no longer be considered a close-ratio, and would not be as good at the track or for cross-country racing.

I agree with you that if the Max was geared differently (so that engine RPMs were lower at highway cruising speed) it would get slightly better highway gas mileage. I would prefer that 2 K RPM were closer to 62 MPH (also 100 KPH). But the Nissan engineers gave us a close ratio 6-speed that is more suited for the track than the interstate. Also, it is geared so that when you are passing someone going 55 MPH, you can pass without having to downshift to a lower gear.

 

never averaged below 22k ever

 

Just drove to vegas, got 23.0mpg average speed was between 70-80

 

SilverMax; you are correct. I get the same readings. My mileage is creeping up a bit, 25MPG and 583 miles on the odometer.

 

I just averaged about 25 mpg on a trip from New York to Orlando then back to New York again.

 

This average mileage is not as informative as segment mileages. I suspect you got worse mileage in the heavy traffic aroung NYC, Phily, Balt & DC and better mileage when out of the heavy traffic driving in southern VA plus NC, SC and GA. When I'm cruising in light traffic on the interstate at between 65 and 70 mph, I can get close to 30 mpg.

 

You are correct. There were areas where I got significantly better MPG than others. I did notice that I got around 26 MPG for over one hour and a half period when I was averaging 81 MPH.

 

I'm taking my baby out on the road from Northern VA to Hollis, Queens, NYC next weekend (Home). That is a nice trip to test my mileage out and should get me past my break-in miles on the way back. I will post my average with the watered down NY gas from the Getty Gas station.

 

not to resurrect a dead topic, but I have a question that is fairly relevant to this subject and if someone could help address it, I would greatly appreciate it.

Recently the mileage indicator screen (I forgot what button to press to get there. I think it is the button under the "trip" button) has been on the fritz. It would hold steady around 22.3 mpg for the first year that I bought it. Today, I started the car after work and the indicator was at zero (actually it was two little asteriks looking thingies) and it went from zero all the way to 27 mpg. It would drop from 27 to 23-24ish depending on whether I was stopped or driving. It went up about .1 mpg each second when I accelerated from zero to highway speeds. From there it took a few minutes to top out at 24.6 initially.


I would imagine the indicator is supposed to be relatively consistent.. it IS an average after all. I am thinking maybe some type of sensor is bad.. any ideas? I don't have the $$ right now to take it to a dealership to have them diagnose the problem.

 

The "Fuel Econ" button is right below the "Trip" button. And it is supposed to be an average "Fuel Econ" reading from the present back to when this measurement was last reset.

It does sound like a sensor (or a computer segment) is not functioning properly. The way you reset this reading is to hold this button down until it resets (about 10 seconds). You might try that to see if you can get a good reading again.

I reset this reading on my Max every time I fill the tank. I note the reading in a book and also the gallons and miles traveled. Whenever I compare my computer's reading of mileage with the calculated mileage, the results are usually quite close -- so I have tended to stop doing the math calculations of mileage and just use the computer reading as a reasonable measurement of what my Max is doing.

Good luck with getting this to work for you.

 

I reset my mpg counter this morning and drove about 2 blocks in the city. It displayed 9.2 mpg. Should I be worried?

 

Depending on the city, it sounds about right. But you need to go further.

I suggest you reset it when you fill up with gasoline. Then read it the next time you fill up and compare the computer reading with the manual calculation of miles per gallon. The two should be reasonably close (if you fill the tank to about the same level each time you fill the tank up).

Hope this helps.

 

Yup I'll do this thanks. I do feel a little better about the situation because I reset it again this morning and drove the same two blocks like a granny and it displayed 19-20 mpg. I'm ok with that. As long as my driiving habits are the problem and not a mechanical failure of the car.