What fuel do you use?

[2018ExpyPlatinum]

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.

 

[Fastcar]

I've been reading for years about the benefits of higher than called for gas. So just for the hell of it I figured I'd do a mileage test on our 2021 Expy 4X4 King Ranch with HD towing 3:73 gearing with 23K miles on it. This truck has given 19.1MPG combined city highway driving since we broke it in using 87. I figured 3 tankfuls using 93 would be telling. A combination of my wife (who does the majority of city) and myself driving and a mix of 60/40 city/ highway miles would tell us something. Soooo..after spending a dollar plus more a gal. for 93 gas our mileage jumped to 19.5MPG. Did it run better? Nope. Was there an increase in performance? Not in the SOP dyno. Was I happy? No, I was out some money for a marginal return.
This isn't the old days when you could crank in some timing or change heat range on the plugs or play with jets. These things are are putor controlled trucks with the areo of a damn brick. It is what it is. A big heavy truck. Enjoy it for what it is. If you want economy buy a compact.

 

[sdinwiddie85]

Does it say in the manual that 91+ is needed for the SPP? I haven't looked.

Not required, you can run 87. Full power rating is 91+.

 

[BravoAlpha]

In regards to TOP TIER - Some Costco are, some not. Same for Wal-Mart/Sam’s Club

I was curious if there was something to it. 5000 miles on 87, 5000 on 91-93
inconclusive.

 

[mdecillis]

Not required, you can run 87. Full power rating is 91+.

So it is required to get the extra power. Does anyone know what the power rating is if you don't use 91+?

 

[2018ExpyPlatinum]

@mdecillis ...As I remember, non 91+ use gives you the standard 375 hp/470 tq.

EDIT:

From the brochure:

"EcoBoost® power delivers up to 400 horsepower *5 and 480 lb.-ft. of torque *5

*5--Horsepower and torque ratings achieved with 93-octane fuel"

OMG....93 octane!! So it's tuned to use 93. You can't even get 93 out west. Guess I'm going back to 87 and say F it.

 

[blkZ28spt]

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

 

[Dahammer]

Since ownership, at the end of May 23, I use premium. Come winter, regular.

 

[2018ExpyPlatinum]

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.

To continue this dead horse, if you're buying your gas from the usual suspects (QT, Circle K, Costco, major travel centers, etc), it IS top tier. Technically, even Joe on the corner is top tier. The only issue with Joe on the corner is how OLD is his gas. Again, it's all pulled out of the same pipeline, tank, trailer. Those "additives" only amount to about 1%, so about an ounce in a gallon. You probably have more "moisture" in that Top Tier gas than "additives". And do you really know if you're getting those additives? Companies pull gas first by price (what supplier is cheapest) then by allocation. I've seen many a load being pulled as "generic" going to name brand stations (think Shell or Sunoco without those advertised "additives") based on price or allocation. And your Costco gas is as generic as it gets. I know too much about the business....I've already told you too much.

 

[Wangle]

Top Tier, always. 87 Ethanol usually. I get almost exactly 10% better mileage with 91 ethanol free. Always Premium when towing.

 

[rd618]

93, by choice.
For those wondering, or those interested in the science, the higher octane helps avoid knocking under load and thus the computer retarding the timing, pulling a slight amount of power.
The only time most people driving todays “87” octane will notice a power difference compared to 91+, is under WOT or Towing. If you’re calling for, let’s guess, 70% or more of the engine’s power capacity, the timing accuracy and octane becomes more critical for maximum output. Below that range the engine is not at the same risk of pre-detonation with 87. Effectively your torque curve and HP output might even be the same.
Keep in mind. We are talking 87 vs ~92. It’s not as severe a jump as say 85 to 104 octane.

 

[rd618]

To continue this dead horse, if you're buying your gas from the usual suspects (QT, Circle K, Costco, major travel centers, etc), it IS top tier. Technically, even Joe on the corner is top tier. The only issue with Joe on the corner is how OLD is his gas. Again, it's all pulled out of the same pipeline, tank, trailer. Those "additives" only amount to about 1%, so about an ounce in a gallon. You probably have more "moisture" in that Top Tier gas than "additives". And do you really know if you're getting those additives? Companies pull gas first by price (what supplier is cheapest) then by allocation. I've seen many a load being pulled as "generic" going to name brand stations (think Shell or Sunoco without those advertised "additives") based on price or allocation. And your Costco gas is as generic as it gets. I know too much about the business....I've already told you too much.

I’ve got a local friend who owns a Gulf, he basically confirmed the same thing you’re saying.
The volume part he said is most critical, they don’t make a lot per gallon so you need to move a lot of gallons.

 

[sixstring]

I buy the cheapest gas Wawa has.

Vehicle runs fine with the cheap stuff.

 

[2018ExpyPlatinum]

@rd618 ....thank you! This dead horse gets beaten so often by so many. Sadly, facts do matter.

 

[Dice Roll]

Try this (I ain't wasting money on 93 octane.)

Is Premium Gas Worth It? We Test High Octane on 4 Popular Vehicles

We tested higher octane fuel than manufacturers require on the Honda CR-V, BMW M5, Ford F-150, and Dodge Charger to see if it impacted acceleration or MPG.

www.caranddriver.com

-- Chuck

That makes a great case for 93. I didn’t buy this thing to save money. That’s huge power and is consistent with my trials with the seat of the pants meter. I sometimes use 89 in winter and to top off 93 for a long trip when I just need a few gallons to start off full. Easier to stop the day before than have an earlier break on travel day.

 

[LG_123]

93 when towing. It gives a big jump in mileage which means fewer stops and it’s not that much more cost-wise since I use less fuel.

I also use premium when towing or loaded with cargo. It ends up being cheaper than regular. Regular is cheaper around town and I drive the car gently in the city anyway.

 

[LG_123]

Have been using Costco 93 octane on all my Ecoboost trucks for years. More power, better fuel mileage and they are Top Tier rated.

I wish Costco had 93 here. The one near us only has 87 and 89. But I only buy Top Tier rated gas, preferably from Costco when I don't need premium.

 

[amanwithaplan]

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.

 

[rd618]

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.

Just a note, your 5mph difference assuming the same weight will easily net you 1-2mpg better. Nothing to do with the fuel. Can you get better mileage with 93 vs 87, yes. But we are talking .4-.6 mpg.

 

[amanwithaplan]

Just a note, your 5mph difference assuming the same weight will easily net you 1-2mpg better. Nothing to do with the fuel. Can you get better mileage with 93 vs 87, yes. But we are talking .4-.6 mpg.

Agreed - just wanted to note the reason for putting 89+ and going slower, otherwise, I should've mentioned above that throughout the ownership of the SUV and in my experience, regular 87 octane fuel (from a reputable station) is perfectly fine.