So I had been getting consistently 16.5 to 16.7 mpg from my drive to work and back. I baby it and that's what I get. I put in 89 octane while towing my boat a couple weekends ago and when I returned I had a half tank. Got 12.7 pulling by the way... Anyway, reset the MPG computer when I returned and when I looked a couple days later it was at 18.7 mpg. I filled up one more tank with 89 to see if a fluke and low and behold I am getting between 18.7 and 19.0 mpg. This seems crazy? It is about a 12% improvement, but the gas costs about 12% more too. Anyone else tried or noticed this, or have my new tires just broke in enough that I can expect this MPG all the time.
89 Octane
- Thread starter Nate03
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jeff kushner
Full Access Members
Nope, not a fluke....my Average-since-new is 18mpg and tanks typically yield 19 to 19.7 now with 42K on the clock. I use 93ron and have since day one but I very seriously doubt that 93 would yield less mileage since it actually burns slower.
jeff
jeff
MidwestBoater
Full Access Members
Similar experience here.. We tow our boat to the same lake almost every weekend and take the same route.. The first two trips of the season we got around 9.5mpg for the 180 mile round trip on 87 octane, the last three trips i've used 89 octane and got anywhere from 10.5 to 11.5mpg. 2016 Expedition XLT 4wd, short wheelbase.
Well I was looking at other F150 forums and they claim it did not make a difference, but those are all older posts from 2013 or older. I just can't believe the difference I am seeing though. It's impressive. Makes me wonder if running 87 octane is bad for the engine. Anyway, I am now only running 89 octane. Peace of mind is worth it I guess. I wish it wasn't so much more expensive here though. It's 30 cents a gallon more.
Im surprised at the magnitude of the mpg increase here, but not the concept. 07XLN explained here a while back that the Ecoboost engine technology has the ability to adjust engine operating parameters and optimize combustion to the octane level. For example the timing can be advanced for higher octane fuels without knocking ... More efficient combustion and better mpg. He can explain it a lot better than me. I'm an antique trying to catch up with new technology.
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The manual reccomended using a higher octane fuel when towing or in hot weather, so even though it can run 87 just fine, the ecoboost does better with a higher grade fuel. I run an 87 octane tune and fill up with 89 when towing and it does make a welcome difference in towing mpg.
powerboatr
Full Access Members
we almost always use 92..once in awhile i get the 89, if the place is out.
but 92 is safe to say 98% of time.
I did run 87 non ethanol in my f150 eco boost and it made a huge impact on mpg, but the cost per gallon was not worth the extra mpg.
so 92 grocery store fuel. we still get 17.5 city and 19 on highway at sustained 75 mph, it fluctuates but eventually settles at 19 as a solid figure
i use 17 as a gauge for trips so i plan fuel station stops.
i use 7 for the bus
but 92 is safe to say 98% of time.
I did run 87 non ethanol in my f150 eco boost and it made a huge impact on mpg, but the cost per gallon was not worth the extra mpg.
so 92 grocery store fuel. we still get 17.5 city and 19 on highway at sustained 75 mph, it fluctuates but eventually settles at 19 as a solid figure
i use 17 as a gauge for trips so i plan fuel station stops.
i use 7 for the bus
JExpedition07
That One Member
It’s not so much that it changes to run better with higher octane it’s more that it’s designed to run on higher octane, and it’s peak power output and fuel economy (manufacturer figures) are achieved on premium fuel. When you put in lower octane fuel the motor retards timing. It’s all in the Variable Cam Timing on these modern motors.
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ExpeditionAndy
Full Access Members
Put 93, in it on our trip out to PA averaged 17.3 MPG. I averaged 14.1 going back and forth to work using 87.
My '16 Expy I only run Top Tier fuel such as Shell Premium or Mobil since the day I drove it off the lot. I like the all around engine performance that makes up for the missing 2 cylinders. Makes the truck fun to drive.
Helo driver
Active Member
Always run BP Ultimate 93 octane. Clear fuel that will keep the system cleaner. That’s right from a chemical engineer in the family. I run nothing but BP 93 and I also have a K&N air filter. 21 MPG average now with 9400 on the clock..
BP is also my choice of fuels, we have company cards for BP, Shell and Mobil. All my vehicles have K&N air filters.
Savannah Dan
Active Member
I ran tanks of 87, 89, and 93 in my 2017 to check the mileage. I don't have the numbers in front of me, but the higher the octane, the better the MPG. Ran a bit stronger too. I calculated the cost per mile for each. 89 was about $.15 a mile and 93 was about $.17 a mile to drive.
chuck s
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Yep, the EcoBoost engines are well documented to put out more power and get more mpg with higher octane fuels. The question remains a matter of economics. Dan's experience indicates 93 octane costs 12% more per mile than 89. And, I'm sure, even more than 87 which runs fine in my truck.
Ya gotta decide what's good enough for your use. For me that's good ole 87. I have another car that requires (and is tuned for) 93 Octane and this runs a consistent 60¢/gallon more than 87 here in Virginia regardless of the price of 87.
-- Chuck
Ya gotta decide what's good enough for your use. For me that's good ole 87. I have another car that requires (and is tuned for) 93 Octane and this runs a consistent 60¢/gallon more than 87 here in Virginia regardless of the price of 87.
-- Chuck
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