Recently, I took a trip from TX to FL and I had a 2017 Maxima S rental with 3600mi on it, returned it with 7200mi on it a week later I figured I'd test out how different octanes affected MPG on a long trip. All gas fill-ups were at Shell and I started with a full tank of 87, tires were all set to 33psi. I set the cruise for 75 and stuck to that pretty well, here were my results - all hand calculated:

87 octane - 489.5mi traveled - 16.3gal fill-up = 30.03mpg
89 octane - 510.1mi traveled - 16.0gal fill-up = 31.88mpg (6.16% increase)
93 octane - 519.5mi traveled - 16.2gal fill-up = 32.06mpg (.56% increase over 89 octane, 6.75% incease over 87 octane)

Here are the prices I paid for gas (this includes any Fuel Rewards discounts I had):

87 octane - $1.89/gal
89 octane - $2.13/gal (12.69% price increase)
93 octane - $2.69/gal (26.29% price increase over 89, 42.32% price increase over 87)

Factoring out the performance aspect of the different octanes, I can say from this data that on a long road trip, it is not cost effective to use a higher octane gas, as the price increase for the higher octanes is far larger than the mpg increase.

Other interesting things to note:

• The trip computer MPG overestimated fuel economy by about 10%
• The highest DTE (distance til empty) that I saw was 572mi

Even knowing this, I know that 93 burns better and is better on the motor, I would still use 93 if this was my personal car. I just thought this little experiment was interesting on a rental.

 

Very interesting information and analysis. I'm curious, may I ask what your profession is? Is it analytics-based?

Anyhow, to almost average 75mph and get 30+mpg is fairly impressive for a 300hp V6 engine. At least to me that is. Could be wrong.

 

I'm a Software Engineer, but I enjoy little things like this cause I like math

But yeah, I'm very impressed with the performance and gas mileage of this car, thinking about a Maxima again when my 14 GLi lease is up.

 

Thanks for performing that task! I'm certain many members here will appreciate it!

To share my experience... My wife and I just bought a 2017. We drove it from Luling, LA to Magnolia, TX. Running at 72 - 75 mph most of the way, we got 33.1 mpg with 93 Octane. That figure was hand calculated. We were also pleased that the Maxima's DIC showed exactly the same mileage. It was dead on spot. I've never had a vehicle that was perfect before. Every vehicle I've owned has always been at least 1/2 mpg high on the DIC. The only thing that would be different on our car is that we had the Dealer swap the Medallion wheels for the SR wheels. The SR tire "might" have a little different revs/mile than the standard?

All that said, we are very tickled to have a full size sedan, with enough power to make it fun, that gets over 30 mpg HWY!

Thanks,
Lou

 

In the 2017 models does your guys have the apple/google carplay? If so how does it perform?

 

Yes, the 2017 does have CarPlay. That was one of the reasons my wife wanted the 2017 over the 2016. I have the CarPlay in my 2016 GMC Sierra Denali and she's always liked to use it. It works just as well in the Maxima as it does in our GMC.

The only thing I like better about the GMC is that you can access Siri over blue-tooth by just "long-pressing" the steering wheel talk button. This does not work on the Maxima. With the Maxima, you have to have your phone plugged into USB#1 for this to work :-(

Lou

 

I recently had a 1,500+ mile trip with my '16 Max. So we had a full complement of luggage and gifts.

I set the cruise at 72-73, which we maintained except for getting off the Interstate to get lunch (had to wait through two stoplights to get back on), and one section of about 15-20 miles of 60-65 around the Indianapolis beltway, and one section of 8-10 miles at 20-45 because of construction. Most of the time was with A/C on.

My average for the trip was slightly over 36 mpg going out, and slightly under 36 coming home - according to the on-board monitor. I did hand calculate one tank (308 miles on 8.151 gallons) that came out to 37.8 mpg. I may not have gotten that tank completely full, as I might have squeezed another 0.2 to 0.3 gallons in. If I use 8.4 gallons, that comes out to 36.6 mpg.

 

Where are Earth do you live!!! Here in California, 89 gas is 10 cents more than 87, and 91 gas is 10 cents more than 89. The delta between 87 and 93 where you live is nuts!!

Based on your calculations, and assuming one lived in California, I assume your conclusions would be different? I haven't crunched the numbers yet....

 

Gasoline prices vary widely. Around where I live (middle Georgia), there have been many times during the last ten years when 89 octane was between 30 and 40 cents per gallon more than 87 octane, and 93 octane was 20 cents per gallon more than 89 octane. That has changed with the price of gasoline down quite a bit in recent years, but will be back when prices rise again.

The entire purpose of such marketing shenanigans is so the dealer can have a big sign showing the very low price of 87 octane, and the customer does not know how much the 89 and 93 are until he gets right beside the pump. At stations where the prices of all three octanes are visible from the roadway, the prices tend to be much closer.