Ok guys...getting good MPG's is kind of a game for me. As a disclaimer upfront...I know the G...and even worse...the G - AWD is not the car to get good gas mileage in...but its fun to try anyways and even see if I can tweak the car for more mpg's and power.

So...I'm an easy driver. Using the computer as a guide....i've been tracking the mileage. I know I know...its not 100% accurate, but neither is a dyno vs. another dyno. But if you use a dyno as a guide..you can track HP increases...so..I'm doing that with the computer.

So...two tanks back...my car avg like 17.9..pretty lame. My Altima SE-R was always in the 20's...and High 20's if I was on a road trip most of the week.

I thought, this car is just breaking in. The next tank (last week), I was able to eek out an avg of 21.5-22mpg. Not awesome, but respectable considering about 40% of that is in the city.

So now the real test.....I had to travel about 70 miles away from my office with my car this past friday. On my way back to my office from my job site, I had to fill up. Perfect, full tank, reset everything to zero and started on my way.

First 35 miles is rural highway, two big hills, 55mph speed limit...a few quick towns where you need to drop to 35mph for 2-3 miles.

Second 35 miles is NYS Thruway, 65mph speed limit.

Hyper-miling...never going above the speedlimt, crusie control at 65mph on the thruway. 09 G37X 7AT, driver, no a/c.

Average mpg: 31.9mpg at the end of the trip!!!!!

I was up near 33.5 after the first 35 miles since I kept the speed around 55mph.


So all this has me thinking about increasing the mpg. I might swith to Mobil 1 0W-30 vs. the stock 5w-30. They claim 2% better economy. That could be another .5mpg or so.

Also, i'm conviced the wheels are a major drag on mpg AND hp. The 09 sport rims weight ~30lbs according to a fellow memeber here. I bet the 07-08 sport 18inch rim is basically the same. Now...what if I swap that out with some 18lbs Volks, that woudl be saving 12lbs per wheel X 4 = 48lbs of rotational mass. That seems like it would be pretty significant.

SO...wonder what kind of mpg i could get on the same route with a 7AT Sedan RWD. 150lbs lighter and no AWD drag.

Food for thought.

Mike S.

 

I'm averaging about 20 mpg mixed on a RWD 7AT. I'm only at about 2k miles so I think my gas mileage will improve. I don;t have a good benchmark for long distance highway mileage yet but I'm impressed with your numbers.

 

I have not had my G37 journey rwd all that long, and have been (attempting) to drive it accordingly for the break in period.
I just filled up today and recorded 20 mpg for mostly (80% or more) in town driving. I managed just over 19 for the first fill up which was all in-town short hops of less than 10 miles.
I think the 3.7 can get better as time passes and the engine gets thru the break in period to loosen up a bit. But most people tend to start driving more agressively once break in is completed. Hard habit to get away from when the power is there.
The 09's like mine don't have the problem with initial throttle tip-in as previous models did and that is bound to help with in town stop and go driving. Previous models were just way too aggressive and hard to take off smoothly with. It could not have helped the mileage any.

Oh, and the computer on my car is about as accurate as trying to figure it all manually.
The computer said 19.7 mpg, when I went 239.7 miles on 11.9 gallons of premium. (Just over 20 figured manually)
The only way to get more accurate would to be driving the exact same way over several fills, and only using the same station and pump to refuel, then look at the average.

The key to good mileage in town is not trying to be the quickest away from the light, but using slow and moderate acceleration, hold a steady pace and coast when you can. The engine has enough torque to loaf along, but most G drivers would not tend to drive that way.

 

My '09 sedan 7AT RWD has 4800 miles now and one oil change. I routinely drive 70 hwy/30 city and get 25.5 to 26.5 mpg by pencil & paper method. I checked the car readout and it has 25.8 avg. I went on a mostly hwy trip recently and measured 29.8 on one tank and 30.1 on the second cruising at about 65 to 70 mph. If anybody is complaining about that then your standards are too high for a car with this horsepower! That is what I consider excellent mpg!

Herkypilot

 

I agree, that's excellent mileage.
What's your driving style to get this mileage?

 

great mileage!

i dont know about changing to 0w/30 oil... i might be very thin for the motor.

 

i get 12.7 mpg...fml....

 

I'm averaging 19.5 mpg with 50 city / 50 freeway; but I live in Southern CA where traffic is seldom moving during the day

 

You, sir, are probably using basic hypermiling techniques without even knowing it

to you!

 

How does anyone drive one of these 70 on the highway? I will be cruising, look down and find that I am going 90.

Even so I average 21-22 for my 110 mile(about 2/3 highway) a day commute. I am very happy with that.

 

I just turn on the cruise control...I do agree it takes some self-restraint to keep from burying the pedal all the time, but just because the power is there doesn't mean you always have to use it.

I occasionally get on it when needed just to enjoy the day a little more. These cars sound great just cruising around with the windows down and you step on it.

Herkypilot

 

Oh, those little buttons on the right side of the steering wheel! More fun to pass people.

 

Yeah .. this G37x bites in mileage compared to my TL which got about 28mph highway .. this thing is no better than about 19 so far... oh well -- power >> mileage (IMHO)

 

Power defiantely > Milage. My dad's Acura TL gets over 30 on the highway, but I dont want to drive it unless I have to. FWD = boring IMHO.

In my G37Xs 7AT I am getting around 27 on the highway when cruising but in the city.... stopngo = 12-14mpg

 

I'm getting ~ 20 mpg around town. I just did my first real road trip where it was roughly 50/50 highway/divided highway with some stop lights and small towns with speed traps, and I got 29.4 mpg. This is actual calculated mileage and not what was on the trip computer. Pretty amazing to say the least. The car is absolutely awesome on the road!