@Adi
Exactly. Premium is $1 more per gallon here. If it was cheaper, I’d use it. But I’m not paying an extra $150 a month just for slightly better performance.
@Adi
You’re right, regular gas has more regulations than people think. In fact, at some stations, mid-grade is just a mix of premium and regular. Most work trucks run fine on 87. As long as you maintain the truck, it’ll last. If you’re towing, just throw in some octane booster or fill up with 91. Proper maintenance is way more important than the octane level.
Use quality 87 gas, and switch to higher octane only when towing. Save the money you’d spend on premium and put it towards more frequent oil changes for better engine health.
For turbocharged engines like the 2.7, it’s best to use the highest octane you can afford. Even though modern knock sensors can help prevent damage, they only kick in after detonation occurs. So with lower octane gas, you’re still putting more stress on the engine, which can wear it out faster.
I always use ethanol-free fuel.
True said:
I always use ethanol-free fuel.
Someone’s got deep pockets. 
True said:
I always use ethanol-free fuel.
I tried ethanol-free over the winter and definitely noticed better performance and mileage. Usually, though, I run 91 or 93.
Octane doesn’t impact how clean your engine stays. If you want to keep your engine clean, just use it regularly. Drive it hard enough to get it up to temp and keep it there for a while. Skip the snake oil fuel additives, they’re a waste of money.
@Nash
This advice is wrong. You need to run at least mid-grade in the 2.7 or 3.5 Ecoboost engines. Lower octane gas will cause issues with the catalytic converters over time, and the engines won’t run as efficiently.
I use 87 from Costco (which is top-tier gas) or 93 when I’m towing or driving in the mountains. Never had any issues.
I use 91 for a cleaner burn and a slight boost in horsepower.
I use 87 for everyday driving and 93 when I’m towing. Honestly, the difference in power is minimal. I’ve even raced a buddy with a similar F-150, and it was dead even when I was running 87. These engines are built to handle it. What’s more important is keeping up with oil changes and regular maintenance.
87 or premium?
I use 89 in my 2.7 and 91 or 93 in my 3.5 whenever I can find it.
93 is best, but it’s more expensive. Maybe throw in a bottle of Techron every other month and stick with 87 the rest of the time.
Anyone tried E15 when it’s on sale?
Yeah, it costs more, but I always use 93.
I’ve got a 2021 3.5 Ecoboost and only use 87. I get close to 21mpg in town and over 24 on the highway. Just make sure to get the Ecoboost service done every 40-50k miles.
The manual doesn’t say you need premium fuel. It’s not a high-performance sports car. I’ve never seen anyone’s engine blow up from using 87.
I’ve got a 2017 2.7 and used to run 87 but switched to 92 after noticing it performed better on steep hills. It’s more expensive, but I usually go to Sam’s Club, so it’s cheaper than other places. Last week I paid $3.28 per gallon for 92.