What Octane Gas Are You Going To Put In Your JL?

What octane gas are you planning on running in your JL?


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AZCrawl

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The owner's manual states that 87 octane is all that is required in the 3.6L V6. Besides the cost of putting in 91 octane fuel, are their any downsides to running it? Could there also be pro's such as power gains, cleaner internals, etc.?

I am used to running 91 octane in my Tacoma that I just sold, but would like to save the money if there is no real benefit to running 91 in the JL.
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jeppesen.io

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Unless your engine can use the octane, it does nothing. All it does is help with knocking (detonation). The updated 3.6 still has a low compression of something like 11.3 to 1, so no need for high octane.

I, for one will be happy to have my first vehicle ever that does not need 91
 

OscarMike_to_Rubi

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Instead of 87/91 dilemma, and if you're in the mood to fool around, I'd try running a few tanks of ethanol free fuel.

Most of gas where I am is 90/10. The 100% is priced similar to mid / premium where I am, but allegedly delivers better mileage. I've contemplated, but never done it.
 

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Besides the cost of putting in 91 octane fuel, are their any downsides to running it? Could there also be pro's such as power gains, cleaner internals, etc.?

Best way to throw money away is give your engine higher octane fuel than it requires.
The octane rating is not the only parameter in expensive fuel. Some fuels are cleaner than others and contain less Sulphur. As this tends to be more expensive, companies "bundle" cleaner fuel with higher octane fuel in the cases I know. Low octane fuel is what budget conscious people use and I think the fuel companies try to keep the costs to a minimum with them, fwiw.

Unless your engine can use the octane, it does nothing. All it does is help with knocking (detonation). The updated 3.6 still has a low compression of something like 11.3 to 1, so no need for high octane.

I, for one will be happy to have my first vehicle ever that does not need 91
Have you had a stock pentastar before? Over here in Australia, the label says to use 91 RON but using 95 definitely makes even the JK-gen Pentastar with lower compression sound smoother under load in low RPMs. The manual itself says that a bit of pinging/knocking is natural and I'm guessing the higher octane reduces that.

I run BP 98 RON on my JK because mine's supercharged and tuned for it. Will be doing that to the JL too unless FCA announces a V8 option... which will make me run it stock for maybe 6 months :D
 

Karl_in_Chicago

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The owner's manual states that 87 octane is all that is required in the 3.6L V6. Besides the cost of putting in 91 octane fuel, are their any downsides to running it? Could there also be pro's such as power gains, cleaner internals, etc.?

I am used to running 91 octane in my Tacoma that I just sold, but would like to save the money if there is no real benefit to running 91 in the JL.
There is no benefit except to the shareholders of whichever oil company's gas you are buying.
 

DanW

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I'll run only Top Tier rated fuel, as in my JK. However, I'll occasionally run 91 octane ethanol free fuel. I don't care about the 91 octane, but it has more btu's per given amount of fuel than 10% ethanol blends. I can feel the difference in my JK, and it picks up about 1/2 mpg, too. I don't run it often, though, because it is expensive. I mainly run that stuff in my Evinrude boat motor and Polaris Rzr. My JL is running perfectly on 87 octane Shell gasoline. That's all it has had so far, except for the full tank the dealer delivered it with. That was probably cheaper non-Top Tier fuel. It ran fine on it anyway.
 

Jtimbrook

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Here in the Southwest our options normally are 86, 88, and some 90-something dependent on the gas station. My 2012 so far has done well on the 86 but I think paying the extra for 88 might work out better...
 

Karl_in_Chicago

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I'll run only Top Tier rated fuel, as in my JK. However, I'll occasionally run 91 octane ethanol free fuel. I don't care about the 91 octane, but it has more btu's per given amount of fuel than 10% ethanol blends. I can feel the difference in my JK, and it picks up about 1/2 mpg, too. I don't run it often, though, because it is expensive. I mainly run that stuff in my Evinrude boat motor and Polaris Rzr. My JL is running perfectly on 87 octane Shell gasoline. That's all it has had so far, except for the full tank the dealer delivered it with. That was probably cheaper non-Top Tier fuel. It ran fine on it anyway.
If I could run ethanol-free fuel I'd do it all day long. Round these parts it's mandated a minimum 10% ethanol blend - because Big Agra.
 

Jeeptimus Prime

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Depends on which engine I get.

The 3.6 def get 100 octane to get the full 840HP! Ok ok...just recently saw a video on the Demon...a man can dream can’t he?!?

Also is there really top tier fuel? US has standards for fuel and most if not all gas companies get the same base gas (gas is gas) but some add special blends which is mostly just marketing mumbo-jumbo to charge more. CA likes to reduce octane and add ethenol effectively making it cheaper gas while charging more tax for it making it expensive gas...lol.
 
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DanW

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If I could run ethanol-free fuel I'd do it all day long. Round these parts it's mandated a minimum 10% ethanol blend - because Big Agra.
Get an app called Pure Gas. It will tell you where to find it. Usually, you'll see it at Co-Ops. Sunoco sometimes has a "Powersports" labeled pump and they make it sound like it is for boats and off-road toys. Anyway, that app will help you find it. I know about the Big Ag deal, but it is funny how those farmers seem to want ethanol free at their Co-Ops. Hmmm.
 

DanW

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Depends on which engine I get.

The 3.6 def get 100 octane to get the full 840HP! Ok ok...just recently saw a video on the Demon...a man can dream can’t he?!?

Also is there really top tier fuel? US has standards for fuel and most if not all gas companies get the same base gas (gas is gas) but some add special blends which is mostly just marketing mumbo-jumbo to charge more. CA likes to reduce octane and add ethenol effectively making it cheaper gas while charging more tax for it making it expensive gas...lol.
Yes! GM, Honda, BMW, and others came together and created the standard. http://www.toptiergas.com There are minimum EPA requirements for detergent, but Top Tier exceeds those standards. Shell, Exxon, Mobil, Chevron, sometimes Phillips 66, Country Mark, and some others are Top Tier. Some BP stations are, but many of them are not. Gas Buddy App, I think, will sometimes tell you. Shell, Mobil, and Chevron are ALWAYS Top Tier.

Around my area, they'll tell you all the gas comes from the same refinery, no matter the brand. That's true, but the additive package is proprietary for each brand. The refinery also has their own options a fueler can specify. The additive pack is what separates the good from the bad. If I ran cheap gas in my JK for a few tanks, the knocking/pinging would get noticeable. I then run two tanks of Shell V-Power, and it cleans the crap out, along with a couple Italian tune-ups, of course. Then, when I go back to Shell 87, the problem does not return until I run cheap gas again.
 

TXRubicon

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Anything higher than 87 in a Pentastar is a complete and total waste of money, but if it makes you feel better it won't hurt anything. It will make ZERO difference operationally.
 
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