Quickest and safest way to go from 87 Octane to 91 Octane

Mfarr75

Well-Known Member
Joined
Jul 2, 2020
Messages
252
Reaction score
752
Location
Milky Way Galaxy, Third Planet from Sun
Vehicle(s)
2021 JLUS
Occupation
Aspiring Lottery Winner
You seem a little frustrated and bitter. But have a nice day anyway and hope life takes a positive turn for you.
And oh, here the regular gas is 87 octane and not 89. And back in 2018, the owners manual specified 91 octane only for the 2.0L. They changed the specs next year to 87 octane acceptable but 91 recommended.
Nah, I'm fine but thanks for asking. And thanks also for the well wishes on a positive turn in my life. It's always quaint when people say that when they really intend it as an insult. Now, my definition of "posiitve turn" may be different than yours. In fact I am sure it is, since my positive life turn involves a powerball win, a penthouse hotel room in Vegas, and Jennifer Aniston. Who knows, maybe it will happen!

I just like to have some fun with the more bizarre and frankly dumb questions that come along. Yours is very high on that list, but I am sure you figured that out already. Anyway, it sounds like maybe you resolved your conundrum about the gas. I guess you needed to float that one by a bunch of internet strangers to understand how to add new gas to your jeep.

Come back and see us soon for answers to other questions you will surely have, such as "My tires are low on air, how do I fill them up with new and different air?", or "I don't like the radio station playing in my Jeep, how do I change it to a different channel?"
Advertisement

 
Last edited:
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Messages
446
Reaction score
213
Location
Las Vegas, NV
Vehicle(s)
Jeep Wrangler JL Willys Unlimited 2021 3.0L EcoD, Dodge Durango R/T 2019
Occupation
Network Architect & Engineer
Nah, I'm fine but thanks for asking. And thanks also for the well wishes on a positive turn in my life. It's always quaint when people say that when they really intend it as an insult. Now, my definition of "posiitve turn" may be different than yours. In fact I am sure it is, since my positive life turn involves a powerball win, a penthouse hotel room in Vegas, and Jennifer Aniston. Who knows, maybe it will happen!

I just like to have some fun with the more bizarre and frankly dumb questions that come along. Yours is very high on that list, but I am sure you figured that out already. Anyway, it sounds like maybe you resolved your conundrum about the gas. I guess you needed to float that one by a bunch of internet strangers to understand how to add new gas to your jeep.

Come back and see us soon for answers to other questions you will surely have, such as "My tires are low on air, how do I fill them up with new and different air?", or "I don't like the radio station playing in my Jeep, how do I change it to a different channel?"
Coming from a guy who thinks the lowest octane is 89. But my question was to make up for the difference of 4 octanes, whether I should fill it with 100 octane fuel or just empty the 87 out and fill up with the specified 91. New Jeep and I didn't know if driving at 4 octanes lower than specified for the engine would cause some issues to the engine.
But if it gives a boost to your low self esteem, I will play along.
 
Last edited:

Mfarr75

Well-Known Member
Joined
Jul 2, 2020
Messages
252
Reaction score
752
Location
Milky Way Galaxy, Third Planet from Sun
Vehicle(s)
2021 JLUS
Occupation
Aspiring Lottery Winner
Coming from a guy who thinks the lowest octane is 89. But my question was to make up for the difference of 4 octanes, whether I should fill it with 100 octane fuel or just empty the 87 out and fill up with the specified 91. New Jeep and I didn't know if driving at 4 octanes lower than specified for the engine would cause some issues to the engine.
But if it gives a boost to your low self esteem, I will play along.
Drink 89 octane, and then just piss in the tank 6 hours later. Your system will dilute the octane down to that 87 number you like, or don't like, or not sure about, or maybe 93 is what you need, but then what about the lower octane, and on and on and on. Otherwise, just be a normal person and not overthink stupid stuff like whether your engine will explode just because a lower octane was put in one tank full. Good Lord. I'm done now.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Messages
446
Reaction score
213
Location
Las Vegas, NV
Vehicle(s)
Jeep Wrangler JL Willys Unlimited 2021 3.0L EcoD, Dodge Durango R/T 2019
Occupation
Network Architect & Engineer
Drink 89 octane, and then just piss in the tank 6 hours later. Your system will dilute the octane down to that 87 number you like, or don't like, or not sure about, or maybe 93 is what you need, but then what about the lower octane, and on and on and on. Otherwise, just be a normal person and not overthink stupid stuff like whether your engine will explode just because a lower octane was put in one tank full. Good Lord. I'm done now.
Why are you taking this so seriously and getting so worked up?
Take it easy guy. Relax. Take your meds. And have a great day. Life is too short to get so worked up over trivial things like this.
If my question from years ago offended you so much, I sincerely apologize.
 

Bartholomew

Member
First Name
Bartholomew
Joined
Aug 20, 2021
Messages
20
Reaction score
24
Location
USA
Vehicle(s)
JLUR
Why are you taking this so seriously and getting so worked up?
Take it easy guy. Relax. Take your meds. And have a great day. Life is too short to get so worked up over trivial things like this.
If my question from years ago offended you so much, I sincerely apologize.
He needs a hug
 

Gregj

Well-Known Member
First Name
Greg
Joined
Dec 15, 2018
Messages
1,265
Reaction score
1,731
Location
West Texas
Vehicle(s)
JLU Rubicon, JLU Sport, upgrades in progress!
Man, we run what ever dishwater comes out of the hose with “zero” issues!

Gregj
 

gato

Well-Known Member
Joined
Apr 4, 2021
Messages
553
Reaction score
660
Location
New England
Vehicle(s)
2021 JLUR
A lot of drama in this thread. Ever since Saab invented microphones to listen to cylinder ignition/detonation and Bosch and other invented reliable fuel injection and ignition controls,, engines can adapt to the fuel they are fed.

Unless you are racing and need to wring out every last bit of performance from modern DI/Turbo engines, you will be hard pressed to feel any difference in performance. Jeep sells this engine all over the world and it's fed crappy fuel tens of thousands of times a day.

Here in the east we have 93 octane fuel andI can't tell the difference between 87 and 93. Can't really understand the debate on how to get from 87 to 91 the quickest. But if I had that problem, I'd simply put in 98 or 100 octane unleaded racing fuel or dump an octane booster into the tank.

P.S. When my Artec skid plates showed up early and I wanted to install them and had a full tank, I found out the hard way that there is no easy/cheap way to get all the gas out of the JL to drop the tank. So yes - I'm impatient and drove around for 300 miles to empty the tank.
 

RoadiJeff

Well-Known Member
Joined
May 24, 2020
Messages
385
Reaction score
479
Location
St. Louis
Vehicle(s)
2020 2.0T Recon, 2018 3.6L GC High Altitude
Since the 2019 owner's manual says 87 octane is OK to use in the 2.0 I guess I don't see what the concern is all about if the dealer originally filled it with that.

This engine is designed to meet all emission requirements, and provide satisfactory fuel economy and performance, when using high-quality unleaded “regular” gasoline having an octane rating of 87, as specified by the (R+M)/2 method. The use of 91 or higher octane “premium” gasoline will allow these engines to operate to optimal performance. This increase in performance is most noticeable in hot weather or other heavier load conditions, such as while towing.
 

Bartholomew

Member
First Name
Bartholomew
Joined
Aug 20, 2021
Messages
20
Reaction score
24
Location
USA
Vehicle(s)
JLUR
Since the 2019 owner's manual says 87 octane is OK to use in the 2.0 I guess I don't see what the concern is all about if the dealer originally filled it with that.
Same conversations happening over in Bronco world right now. Ford recommends 91 but says 87 is minimally acceptable. There is research and testing behind their recommendation.

Some people want to follow the recommendations and get miffed that the dealership doesn't care. Some people are good with the minimum requirements. Others go on anecdotal stories of running high spec engines on E85 and not being able to tell the difference.

Jeep went away from the debate and now says to use 87 and higher octanes don't see any benefits.

Heck, Ford came out a few months back and said that the benefits of using 91 were even better than originally reported.

To each their own. Follow the recommendations or go with the minimum, but ignore those saying that they personally can't tell the difference between E85 and 91, and use gas that meets TopTier standards to protect your investment.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Messages
446
Reaction score
213
Location
Las Vegas, NV
Vehicle(s)
Jeep Wrangler JL Willys Unlimited 2021 3.0L EcoD, Dodge Durango R/T 2019
Occupation
Network Architect & Engineer
Since the 2019 owner's manual says 87 octane is OK to use in the 2.0 I guess I don't see what the concern is all about if the dealer originally filled it with that.
Not a concern anymore.
Yes, from 2019 onward, the manual says 87 is OK but 91 recommended. But the 2018 manual only specified 91 octane so it was a concern then to some of us but that was soon alleviated by many more informed members on this forum that the engine is protected by spark retardation.
 

engineXI

Well-Known Member
First Name
jank
Joined
Aug 13, 2021
Messages
90
Reaction score
51
Location
so cal
Vehicle(s)
rubicon
The 2021 manual says to use 87 octane and you can use 91 octane for improved performance in hot weather and towing.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Messages
446
Reaction score
213
Location
Las Vegas, NV
Vehicle(s)
Jeep Wrangler JL Willys Unlimited 2021 3.0L EcoD, Dodge Durango R/T 2019
Occupation
Network Architect & Engineer
The 2021 manual says to use 87 octane and you can use 91 octane for improved performance in hot weather and towing.
Yep, the 2020 manual did too. However the earlier manuals specified only 91 octane for 2.0L with e-torque. On later model FCA discontinued e-torque for all the 2.0L trims except for Sahara. I don't think e-torque or no e-torque had anything to do with it.
 

gato

Well-Known Member
Joined
Apr 4, 2021
Messages
553
Reaction score
660
Location
New England
Vehicle(s)
2021 JLUR
Yep, the 2020 manual did too. However the earlier manuals specified only 91 octane for 2.0L with e-torque. On later model FCA discontinued e-torque for all the 2.0L trims except for Sahara. I don't think e-torque or no e-torque had anything to do with it.
You guys need to know the reason early on 91 was specified in the manual. It was simply for compliance reason. Jeep had only submitted the fuel consumption data and gotten the MPG rating for the stickers with 91 octane. Once they did the testing on 87 and proved to the gbmt that the MPG was the same, they were free to say 87 was ok.

That is all this is about with the manual/placards. Same goes for oil viscosity. And other things. It is not that your 2018 engine will suffer by using 87 octane. It is that the feds and California won't stamp it as legal for road use.
 
OP
OP
Capricorn

Capricorn

Well-Known Member
Joined
Apr 1, 2018
Messages
446
Reaction score
213
Location
Las Vegas, NV
Vehicle(s)
Jeep Wrangler JL Willys Unlimited 2021 3.0L EcoD, Dodge Durango R/T 2019
Occupation
Network Architect & Engineer
You guys need to know the reason early on 91 was specified in the manual. It was simply for compliance reason. Jeep had only submitted the fuel consumption data and gotten the MPG rating for the stickers with 91 octane. Once they did the testing on 87 and proved to the gbmt that the MPG was the same, they were free to say 87 was ok.

That is all this is about with the manual/placards. Same goes for oil viscosity. And other things. It is not that your 2018 engine will suffer by using 87 octane. It is that the feds and California won't stamp it as legal for road use.
Ah, that makes sense.
 

PeteZ

Member
Joined
Jun 27, 2021
Messages
8
Reaction score
17
Location
Oklahoma
Vehicle(s)
20 JL Rubicon
well this post clears up a whole lotta stuff for me, I will be switching back to 87, 91 was getting expensive and it won't hurt my engine, thanks guy's
 
Advertisement

ATO4x4
 
Advertisement
Top