Premium Gas Question

thompwil · 08-05-2018, 06:17 PM

Howdy,

Is anyone using premium gas in their 2018 V10? The owner’s manual states it’s designed to run on 87, but then states they recommend 91 or higher. Just curious…

http://www.fordservicecontent.com/Fo...userMarket=USA

Thanks

Jim_HiTek · 08-12-2018, 08:12 AM

I have a diesel but I remember reading somewhere that the for gas engines 87 is fine for most use but if you were going to be driving in mountainous terrain, pulling a trailer, or in the heat with the A/C on the 91 would help a bit. Don't remember all the details though.

And that link you posted pretty much says the same thing. Use higher octane in the mountains and those other situations. Back in the day when I had a Ford Ranger that I used as a daily driver, I'd use 91 octane 4 times per year and 87 all the rest of the time. But I was commuting in a city so not too many mountains.

Al Lewis · 08-12-2018, 12:54 PM

I just traded in a 2000 Storm with the Triton V10 and all I ever used was 87 octane gas. Unless the engine is at least 9.3:1 compression ratio high test is wasted. The Ford Triton V10 is 9.2:1. It will run both but the 87 should be fine. The higher octane fuel is just harder to ignite so under the high compression of some engines 87 octane would ignite under pressure before the plug fires causing knocking or pinging. 91 octane won't ignite until the plug fires. I have one fo the Audi S6 V10s and have to use 91 octane as it's 12.5:1. If I put regular gas in it the gas would pre-ignite in the cylinders. At 9.2:1 that is not an issue.

bodycoach2 · 08-17-2018, 07:18 AM

My 2016 35F runs fine on 87 on flat land here in Florida, but I would definitely go to premium if I planned to do any uphill travelling.

**creativepart** · 08-17-2018, 07:28 AM

The price difference between 87 octane and 91 octane would really make an 80 gal fill up painful. It would have to make a huge improvement in performance or mileage or both to get me to pay that cost.

We travel West in the mountains at least once a year and I’ve never had an issue running regular gas.

thompwil · 12-20-2018, 06:49 AM

EDIT: OOPS, Posted This Reply on the Wrong Thread !!

FWIW I started using 89 octane this past Summer. The cost of 91 or 92 is just too crazy here in PA for an experiment, though I may try a couple tanks next month as we head to the SW cost permitting. No increase in fuel mileage was seen though I did notice a "seat of the pants" improvement in engine smoothness, nothing I can quantify with data, just seems to run a bit better. Perhaps a placebo, but the Mrs. noticed it too.

From the Ford manual;
Tells you it's designed to run on 87 then tells you it's recommended to use 91. Go figure.

luvlabs · 12-20-2018, 08:18 AM

That's the same wording used in my 2019 Ford Escape and at 1.5L, it's quite a bit smaller than the good, old 6.8L V-10. In motorhome use, save your bucks and use 87 octane. You will not get better mileage burning 91 octane or higher but your wallet will be lighter.

thompwil · 12-20-2018, 08:52 AM

Quote:

Originally Posted by luvlabs

That's the same wording used in my 2019 Ford Escape and at 1.5L, it's quite a bit smaller than the good, old 6.8L V-10. In motorhome use, save your bucks and use 87 octane. You will not get better mileage burning 91 octane or higher but your wallet will be lighter.

The cost is a problem for sure with 92, it's not quite as bad for 89. It did take two fillups to notice since I never let it get too far below half a tank. I did point out that no increase in mileage was observed. I have noticed the engine running smoother and a bit quieter. I'll continue running 89 for those reasons. The Mrs. noticed it too and I didn't tell her I was doing anything different. She made a comment about it being not as loud in the mountains. I swear she keeps mental notes of every sound that thing makes. I wish I'd had the forethought to take db readings of before & after though.
Happy Motoring

**creativepart** · 12-20-2018, 09:51 AM

One thing to note, when we travel through and around New Mexico and Colorado - which we do often - their "regular" is 86 octane, not 87. They say it's because of the higher elevations.

I go ahead and use it rather than their Plus which is 88 octane.

Here in South Texas the difference in price between regular and plus is between 20 and 30 cents a gallon.

PS. By the way, we're down to $1.99/gal around here now. Someone told me they saw $1.87 in Lampasas, TX which always seems to have cheaper gas for some reason.

Wayne M · 12-20-2018, 01:12 PM

Some places around here are down to $1.79.9 and some are still runing $2.09.9. I can't figure what anyone would purchase gasoline at $.22 a gallon more just across the street from the lower!

Lowest diesel is $2.52.9

Everything changes and sometimes daily.