When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
A reason for Ford's recommendation to use Premium fuel (higher octane) when towing might be better understood when we consider the following:
1. Octane rating is resistance to pre-ignition (pinging). A higher octane fuel burns slower during the combustion cycle, so...
2. To take advantage of a higher octane fuel, spark ignition timing must be advanced, which our truck's superb onboard powertrain control module (computer) adjusts for by sensing pre-ignition via knock sensing software.
3. Once Premium/higher octane fuel is flowing through the fuel system the timing curve becomes more aggressive with spark advance which results in a higher engine torque output. More torque is a win also for fuel economy.
One may choose to ignore Ford's towing fuel recommendation and continue to run Regular but they won't see maximum torque potential, and fuel mileage may not be as good as it might be.
I've been curious how much a difference it makes running 91 octane on an 87 octane 5* tune. I did make a mistake last time towing into Colorado where fuel drops to 85 octane, and the station I stopped at had 85 and 89 as the premium. Running the 91 tow tune with that fuel probably helped the engine overheat. Towed like a banshee, but ran hot!
I've been curious how much a difference it makes running 91 octane on an 87 octane 5* tune. I did make a mistake last time towing into Colorado where fuel drops to 85 octane, and the station I stopped at had 85 and 89 as the premium. Running the 91 tow tune with that fuel probably helped the engine overheat. Towed like a banshee, but ran hot!
I haven't run hot yet - I have a 2017 with the gen2 ecoboost.
I ran a test on my 386 mile mountainous tow to my inlaws towing my ATV trailer. On regular I averaged 13.8. On premium I averaged 15.5. Regular is $2.30 a gallon and premium is $2.88 so maybe someone less drunk than me can figure out if I am benefiting from premium.
When I tow my camper I'll use premium but for my ATV trailer I'm not sure it's worth it? Someone tell me!
Mileage should improve. And unless you're towing over 7500 on steep grades, regular gas is fine.
I also have a Terry trailer, 20 footer. Weighs around 5000 lbs loaded. I just did a trip through the badlands with some very steep hills and got 11.7 MPG for just under 450 miles using regular gas. Used JUST over a tank. I haven't found a difference towing this, 87 octane, 91 octane, no difference... And this is with the 2.7 ecoboost SuperCrew 4x4 by the way.
The trailer:
And the mileage at the end of the trip:
Last edited by BlackBoost; 08-15-2017 at 01:09 AM.
I've been curious how much a difference it makes running 91 octane on an 87 octane 5* tune. I did make a mistake last time towing into Colorado where fuel drops to 85 octane, and the station I stopped at had 85 and 89 as the premium. Running the 91 tow tune with that fuel probably helped the engine overheat. Towed like a banshee, but ran hot!
Running 91 on a 87 5 star tune you should pick up a little more power and a lot of guys run one octane higher for a safety factor when tuned.
My Ecoboost absolutely got better. When I first got it I was like "oh no, what did I buy!?" After several thousand miles it loosened up and started getting the EPA numbers.
08-14-2017, 10:51 AM
