I saw a post early but it was about a FWD model. I have a 2016 Grand Touring AWD model with 19in wheels. I have been getting about 24.6 MPG. That seems a bit low to me. I know the AWD model gets about 2 miles less combined than the FWD model. Fuelly says I should be getting around 26.5. So 2 mpg diff isn't that much... What are others here getting with the same model?

 

2016 GT AWD, with tech package, 6000 miles on it, 16 mile commute to work, two lane roads, light traffic in morning, moderate in afternoon. Averaging 27.4 MPG


On Interstate, average speed 70-75, I've gotten 29-31 mpg.


What are your driving conditions ??? Stop and go heavy traffic, 24.6 might not be too bad.

 

about 13 miles to work taking a 4 lane freeway for 7 miles or so and then 6 miles street. The street part has a lot of stop and go and highway is normally not to bad. On the way home 18 miles as I take a different route home with 4 on street, 13 highway, and the rest street. I would say the 4 miles on street can be busy street commute and highway is about average. I also normally drive posted speed limits on streets and about 70 on highway. I still have about 900 miles on the car and was waiting till 1000 before I went over 70. Not sure if that is good or not. Only time I really hit the throttle is when I have to merge past someone. That doesn't happen to often.

 

Most cars don't fully break in for ten to twenty thousand miles, and until then, fuel economy can run low. Even then, I had one car not hit its peak mileage until there was well over 140,000 miles on the clock.

 

I find with all my cars that they get about 10% better gas millage with premium (91 or higher octane) than with Regular (typically 85). This may account for the difference.

 

Sorry, not possible unless the specific engine is optimized for higher octane fuel. The thing you may not realize is Regular actually has slightly more power per unit than Premium, however, engines with higher compression ratios can take advantage of the extra thermal efficiency of Premium fuel *IF* they are optimized for it by keeping the timing relatively more advanced.

Long story short, if the manufacturer says the engine is optimized for Regular, then it is a physical impossibility for said engine to get better economy on Premium.

 

shipo, don't disagree with what you're saying but my experience is factual. CX-5 manual states 87 or higher, so hard to tell which level its been "optimized" for. FYI, I run regular in all my vehicles, cost differential for premium does not justify 10% mileage improvement.

 

Don't waste your time typing...

 

This is quite possible as has been reported on another CX5 forum. Lots of contributing factors here like temperature, humidity, roads (hills), stuff that could cause timing to be retarded particularly in warm dry weather to prevent engine knock with 87. You said 85, are you living in a higher elevation? I have experienced a bump in mpg from using 93 octane as well in certain conditions.

 

My CX is in the shop indefinitely at this point until they can find the cause of my abysmal gas mileage. I'm driving a 2016 Mazda6 with the same engine and drive train and getting 28.6 Mpg around the same streets on which I drive my CX, and driven exactly the same way. Before the engineers start crying foul, yes the CX is a rolling brick as compared to the 6, but aero would only make a tremendous difference on the highway, not driving around town.