What fuel do you use?

[2018ExpyPlatinum]

Some info: Running a 2021 Platinum Max w/ 4WD & HDTow package.

Just finished a 5000 mile road trip to Colorado and back with 7 full size adults and a hitch carrier with about 400 LBs. I did not go to a scale, but I think its pretty safe to say on the way there and back, we were close to the GVWR of the SUV. I kept gas receipts/data throughout this trip.

Up until driving back, we only put 87 (not 85) and the vehicle was handling it fine. Based off of the receipts, we did on average about 17.461 MPG on 87 gas (not including the way back from Colorado). This includes the drives up the mountains in Colorado (Aspen Mountain/Pikes Peak/Mt Evans/Grand Mesa), i-70, backroads, etc.

Now comes for the drive back. Before leaving, we filled up on gas from a local gas station and subsequently had a misfire on Cylinder 4. It'd misfire for about 15-20 seconds before returning back to normal, but during the misfire, it'd lose power. Still being a long ways from home, we decided to fill 89/91/93 until we'd get home and to our local dealership. That said, we averaged about 18.598 MPG throughout the trip back from Colorado, with the last stretch (856 miles) averaging about 21.08 MPG.

Things to note: We were mainly doing 75-85 on the highways to Colorado but on the way back, we sort of babied the SUV by not putting too much load so we kept it to 65-70.

As for the misfire, the dealership said that the coil and plug for Cylinder 4 were completely shot and it was replaced under warranty.

One has nothing to do with the other. The reason you got better fuel economy is speed. When we moved out here, I drove the Penske truck while my wife followed me in the Expy at 60-65 mph. She averaged 22-25 mpg. If we're "traveling" and running 75-80, we get the usual 18, maybe 19-20.

 

[z71kris]

So I run 87 normal driving, i used 89 on the way to Myrtle beach and got better than 17, because it raised from 16.4 to 17.1 by the time we got here. I forgot to reset before we left to see the actual on the way. On the way home I’ll reset and run 91+ on the way home to see what I get.

 

[Nytimes770]

I’ve used nothing but 87 for Highway and local. I have felt hesitation including when going in reverse and overall the drive felt weak to mediocre.

For my next road trip when I have a decent load weight I’ll try 89+.

The price difference can be up to 50 cents a gallon right? So that’s like $10 per fillup and over 100k miles can be a few thousand bucks.

 

[Dahammer]

Currently, I'm using premium fuel. I read in the manual that in summer and or towing, premium fuel is suggested.
Come fall/winter, I'll switch to regular fuel.

 

[XeBeast]

So, the take away is obvious. If your car doesn't need premium (per the book) why would you use it? If the good book says 91 or 93 must be used, you suffer without it. If you can use 87, but 91 is recommended, do what you want.

But again, other than octane, gas is gas. It's all the same, brand doesn't matter.

My 1971 C10 recommends Premium fuel.

 

[Hellwig]

I try my best to use a top tier rated fuel station. https://www.toptiergas.com/fuel-stations/ Premium is what I use since the truck seems to run and shift much better in my opinion.

Try to pump more air into your tires and use 87 gas, then feel if the higher tire pressure gives you the same "smooth" feeling as what 93 gas gives you. I am not kidding. I figured this out when I deal with the transmission responses of my 2020 Dodge Charger 3.6 SXT when accelerating.

 

[Hellwig]

Currently, I'm using premium fuel. I read in the manual that in summer and or towing, premium fuel is suggested.
Come fall/winter, I'll switch to regular fuel.

Interestingly, the manual specifically states if any owner uses 85 gas even in high elevation area and the engine fails, the manufacture warranty wouldn't cover the repair. That's my understanding of the wording in the manual.

 

[Hellwig]

Gas is gas...but additives in that gas do vary. Top Tier gas is proven to keep top end parts/back of valves cleaner. And often Top Tier is less expensive than other, so, why not seek it out? Costco, QT, etc.

93 Octane because every Ecoboost owner manual recommends 91+ for best vehicle and engine performance. And I want the best performance. Boosted engines have to pull timing and reduce output and run hotter to run on 87. Which they will. But, they run better on higher octane

Slightly better on 91/93, to be precise. For me personally, it doesn't justify the difference of extra fuel cost.

 

[Hellwig]

I’ve used nothing but 87 for Highway and local. I have felt hesitation including when going in reverse and overall the drive felt weak to mediocre.

For my next road trip when I have a decent load weight I’ll try 89+.

The price difference can be up to 50 cents a gallon right? So that’s like $10 per fillup and over 100k miles can be a few thousand bucks.

I rented a XLT (regular size) in Colorado two weeks ago and only pumped 85 gas into its tank. I didn't feel any hesitation at all. As a matter of fact, it performed extremely well at Glenwood canyon section of I70 west, with endless low RPM torque and silk smooth transmission switch.

 

[BravoAlpha]

the ECU needs to detect the knock and make adjustments If you are switching back and forth between regular and premium.

how quick are we getting the performance for those of us that switch.?