[cwa92464]

I have only had mine a few weeks and I'm very interested because our delta here on Reg vs. Prem is $.50/gal. I have run 1 tank of each with no noticeable diff but going to go back and and test more because they were not apples-to-apples. I'm average 21.2 MPG with mix of city/highway but more city than highway. Either way it's a better option than my previous 2005 car that was doing 15 MPG (so still saving at least $450/yr on gas at a minimum.)

 

[McMoo]

Premium is not required. It’s recommended to get 295 hp but this is the identical engine to the one in the pathfinder where regular is recommended and has 284 hp. Don’t waste your $ for 11 hp...

 

[jonesy84]

First two tanks of fuel I put in my QX60 (2015 model) after I got it were both low-grade 87 octane. Around-town driving mostly, only about 25% of either tank was highway driving to and from work. The MPG stats on the in-dash screen said both tanks were within a few tenths of 18.5 MPG. Three days ago I filled up an empty tank (gas light came on) with 93 octane premium. Had a 1.5 hour trip both directions to the in-laws house. Despite reading several articles with fairly concrete evidence indicating you would likely get no tangible performance differences between using low or high-grade gas, I still thought I would find some benefit to the 93 octane fill up. Yet, once I get home from said trip to in-laws, in-dash MPG gauge said so far on this tank I was getting like 19.3 MPG. VERY SLIGHT increase over the 87 octane performance. But I attribute that increase to the much larger percentage of time spent driving on the highway, as opposed to stoplights and stop signs around town. I found this to be interesting. One thing I don't know is if consistently running low octane fuel for years on end would cause damage to your engine's mechanicals that could otherwise be avoided by using higher octane. I'm really not sure if there is a real accurate way to judge that in the long run. But I will say that for all practical purposes, I don't believe I will be using premium fuel regularly. Most likely I will pour in a bottle of octane booster or fuel injector cleaner in every 4-5 fill ups whenever I can remember to. Here in Ohio (where we have notoriously crappy gas quality anyway), I see no real value added to paying about 30-40 cents more per gallon when it does nothing useful for my performance.

 

[McMoo]

Don’t bother with premium, it’s only “recommended” not required. The pathfinder, which has the same engine, has regular fuel recommended and has a few less horsepower. You won’t get a mpg increase with premium. Use a high quality regular gas from a name brand and be done with it and save a few bucks per fill up.

Now, my 07 G35 which is a much different version of the 3.5 says “premium required” and I always fill that with premium.

 

[Vidgamer]

Interesting. We also have a BMW X1, which has premium “required”. X1 owners report not just a loss of power, but worse MPG. So, it’s not a crazy idea to see if there might be a slight MPG difference here as well. Really nice to have the option of not using premium, though, as it is so much more expensive these days.

 

[gmuney1]

Regular works just fine for me although I haven't tried premium (97)

 

[yeller]

One thing I don't know is if consistently running low octane fuel for years on end would cause damage to your engine's mechanicals that could otherwise be avoided by using higher octane.

Nope, as others have stated the motor automatically compensates and adjusts HP. If you'd not running it hard, you won't notice. 120k on mine and it still runs perfect.

..pour in a bottle of octane booster or fuel injector cleaner in every 4-5 fill ups

Don't waste your money, higher octane does not equal cleaner fuel. Exxon 87 and 92 have the same detergents. Octane is not a quality rating.

 

[golftango]

You don't need premium, unless you have deep pockets.

https://www.autotrader.com/car-news/buying-car-do-you-need-use-premium-gas-228198

https://www.edmunds.com/fuel-economy/to-save-money-on-gas-stop-buying-premium.html

https://www.consumerreports.org/fuel-economy-efficiency/why-you-might-not-actually-need-premium-gas/

Basically I run "top tier" 87 and it's fine.

 

[jonesy84]

to further the school of thought finding the high octane, premium to potentially be a waste of money, the tank I am currently on was filled up w/ 87 octane. And I'm just driving it around Dayton to and from work, kids activities, etc.... and halfway through this tank, my avg MPG currently reads 20.1.....

 

[wpeng5040]

I only use 87 and my non-highway commute can be as high as 26 MPG

 

[Tykerowe]

Just purchased a 2015 QX 60 and I am only using premium as recommended, but the MPG display on the dash is showing an average of 10.5 for mostly NYC inner city driving. Is the dash reading always accurate? Or could there be some issue with the car?

 

[jonesy84]

I only use 87 and my non-highway commute can be as high as 26 MPG

I just saw this. I'm still jealous, for the record..... LOL 0

 

[jonesy84]

Just purchased a 2015 QX 60 and I am only using premium as recommended, but the MPG display on the dash is showing an average of 10.5 for mostly NYC inner city driving. Is the dash reading always accurate? Or could there be some issue with the car?

whoa! that's TERRIBLE mileage.


Something definitely up there. we have certainly established in other threads on here that the readout on the screen is by no means 100% accurate, though to be honest it does seem reasonably close in my opinion (may vary by up to 1 or 2 mpg). But in your case I would think it is likely off by as much a 5 or more mpg, giving it an error of about 50%. we haven't seen anyone truly report it being off by that much ever. but the screen reading takes into account time the engine is running and the car is not moving (which obviously factors into the ongoing MPG equation as 0 mpg during this time, so if you have left it running and had it parked several times for long periods of time, that could do it. I would suggest filling the tank back up to full, reset your trip mileage and also re-zero the MPG screen on the dash, run a whole tank, and then check your mileage manually. Compare that mileage to what is on your screen. Outside of variables like how many more squeezes you do on the handle of the pump, which pump or stations you go to, etc... the numbers should at least be reasonably close. If you find that your mileage calculated by hand really is even close to 10.5, there would HAVE to be something wrong unless you do leave your car parked and running for long periods of time consistently.

 

[jonesy84]

On this topic, just filled up this morning. Had mine in 'sport' mode and drove with no real regard for mileage (ie, somewhat crazy). screen said 19.7 mpg, hand calculations 18.25. then again, avg speed was 29 mph, so I have mostly around town/traffic driving conditions. Plus A/C running the whole time. But a LOOOOONG way off of 26 mpg, and also interesting that hand calculations varied by about 1.5 mpg this time.... interesting.... I switched to 'normal' driving mode, will check back after the next fill up or two to see what this mode produces for mpg by hand vs. the screen reading.

 

[jonesy84]

Just filled up again, made 2 decent-sized round-trips on this tank in 'normal' mode with about 85% highway. Avg speed on highway is usually about 75mph (unless you work in law enforcement, then it's 68). A/C on virtually 100% of the tank, as it is low/mid 90's here recently with HIGH humidity, so A/C is barely optional. Screen said 20.4 mpg, hand calculations showed 20.25, so relatively close between the two. This fill up was with 93 premium, will check mileage again after this tank, though this will likely be majority around-town driving, so the type of driving in that respect will not be apples to apples. But we'll see if there's ANY difference either way. My guess is no, but I'll check back in again after this tank on premium if I can remember to.

 

[Rooster]

Just purchased a 2015 QX 60 and I am only using premium as recommended, but the MPG display on the dash is showing an average of 10.5 for mostly NYC inner city driving. Is the dash reading always accurate? Or could there be some issue with the car?

The dash MPG estimate is optimistic, actually MPG (as calculated by hand at the pump) is usually worse.

10 MPG in New York city driving may or may not be bad...it all depends. How long does it take you to drive 10.5 miles (i.e., is it ten 1.5-mile trips?) How much time is spent sitting still with the engine running? Does it take 30 minutes to go 1.5 miles because most of the time you're sitting still?

 

[jonesy84]

Just filled up again, made 2 decent-sized round-trips on this tank in 'normal' mode with about 85% highway. Avg speed on highway is usually about 75mph (unless you work in law enforcement, then it's 68). A/C on virtually 100% of the tank, as it is low/mid 90's here recently with HIGH humidity, so A/C is barely optional. Screen said 20.4 mpg, hand calculations showed 20.25, so relatively close between the two. This fill up was with 93 premium, will check mileage again after this tank, though this will likely be majority around-town driving, so the type of driving in that respect will not be apples to apples. But we'll see if there's ANY difference either way. My guess is no, but I'll check back in again after this tank on premium if I can remember to.

I just filled up again yesterday, dash reading said avg mpg was 19.9. Hand calculation was 19.6, so pretty close there. As I suspected, my mileage had gone down just slightly with more around town driving and less highway driving (my 'average' speed was only 29mph...). Either way, two takeaways for me personally. one, the dash estimated reading, at least for my vehicle and in my recent experience when I have double checked it, is acceptably close for my needs. It has pretty much always been within .3 or .4 mpg, if not closer. Two, I am not a believer in higher octane gas being of any mileage benefit, at least in my scenario with my qx60 anyway.


The last unscientific 'test' I will do here in the next tank or two, as long as I can remember, is to put the driving mode in ECO, and run a couple of tanks on premium and a couple on regular and see what the mileages look like.

 

[McMoo]

I have never used premium. Last road trip of about 1,000 miles yielded 25 mpg with average speed of 68 mph (which means 75+ mph primarily on the highway). I do like to use eco mode with the adaptive cruise control with the eco pedal off. Otherwise keep it in normal mode and get 21-22 mpg in mixed driving.

 

[hankinsrichard79]

good post! thx for info

 

[Zachary]

There are huge difference on my qX60. I believe the dealer filled in regular. The fuel efficiency was compromised significantly. I was about to complain then I filled in premium. Beautiful. The engine was designed for the premium which I can tell.

Just picked up my new QX 60 and would like to know from you experienced users if you put premium or regular gas in the car. I know the owners manual says the premium is recommended, but is it really necessary?

Please tell me your experiences. Thanks.