What octane and type of fuel does your 4.0 like?
- Thread starter AndyG
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Kiwi TJ
I don't suffer from insanity I enjoy every minute
Supporting Member
Ride of the Month Winner
All sources I can find says RON is used in AU and NZ. So, your 91 is our 87 octane. This is actually a good thing for your TJ, but confusing nonetheless for those comparing numbers.
https://en.m.wikipedia.org/wiki/Octane_rating#Measurement_methods
https://www.ils.co.nz/ils/assets/downloads/SKU TDS/659330.pdf
Kiwi TJ
I don't suffer from insanity I enjoy every minute
Supporting Member
Ride of the Month Winner
mmm ok ...yeah fair enough....still very spendy whichever way you look at it though .
Xposure
TJ Enthusiast
I have a gas station by my house that sells 110 octane race gas.....imagine the crazy powa you can make with that! I bet it’s like running nitrous
Yes it’s a sarcastic joke. LoL
But I did have a separate map for my rx7 that we tuned with the race gas....pretty nice to have it 5 minutes away at a pump. It crushed the wallet though, I haven’t bought it in many years but last time I did it was around $7/gallon.
Yes it’s a sarcastic joke. LoL
But I did have a separate map for my rx7 that we tuned with the race gas....pretty nice to have it 5 minutes away at a pump. It crushed the wallet though, I haven’t bought it in many years but last time I did it was around $7/gallon.
Yeah, those prices you quoted are insane. I thought Canada was expensive.
When possible.. i use the blood of my defeated enemies.
Otherwise shell, chevron, mobile.. the cleaner fuels I try to use. Lowest octane.
Otherwise shell, chevron, mobile.. the cleaner fuels I try to use. Lowest octane.
Shatto
TJ Enthusiast
ANY station selling Top Tier gas is selling fuel as good as the, pick the name of your favorite expensive stations.
When I lived in Concord, California a short while ago, I was surrounded by refineries.
Because I was friends with the manager, I found that Costco bought their up to 100,000 gallons a day of gasoline depending on the price, which changes throughout the day with demand, so it may have come from Shell, Valero, Tosoro, Chevron, ConocoPhillips.
Which begs the question; Why pay more for the same gas?
Yessir, I have heard the same thing from other folks that work for the refineries. Costco is one of the best places to buy fuel since it is so fresh, due to the volume they sell. Some of the small name brand stations don't sell nearly as much fuel and it can potentially sit in the tanks for weeks longer in some cases.
Shatto
TJ Enthusiast
Excluding Costco.. are you saying that Circle K, 711, and AM PM fuel is just as good?
I always thought the detergents gas of Shell.. Mobile.. Chevron... etc, help with deposits and build up.
Of course that could be marketing..
I always thought the detergents gas of Shell.. Mobile.. Chevron... etc, help with deposits and build up.
Of course that could be marketing..
Head Lice
TJ Addict
Jeep designed and built the 4.0L .... their R&D knows what will give good longevity / performance at an acceptable cost.
Jeep recommends 87 octane fuel, and further warns that performance may be affected if using a higher octane fuel.
Why would you do anything different unless the c/r is bumped up ?
Jeep recommends 87 octane fuel, and further warns that performance may be affected if using a higher octane fuel.
Why would you do anything different unless the c/r is bumped up ?
Closest one to me with 87 octane is a 40 mile round trip. Not really a choice for me. Otherwise, I would be happy to run this in my Jeep if the price was competitive.
Curious, I’ve heard some others say top tier is just a marketing gimmick, but I have never seen an actual study to back this claim up. Is there a scientific study done that I can reference? I realize all gas has additives that are mandated, but they are not as concentrated as in the top tier gasolines from what the refinery folk have told me. On the contrary there are studies that do claim top-tier is legit, but I’ll be the first to admit, it is mostly the big corporations and big money pushing it. Is it better for my automobile or the environment? Those are two different things. I would venture to say that in our 4.0 tractor engine, it probably doesn’t matter as much or at all, if there is a difference. In a modern direct injection engine, however, running near stoich all the time with higher compression (and potential intake valve carbon buildup issues), I will fail on the safe side with top tier. Anyhow, I don’t see a reason to run the cheap stuff over top tier either way since the cost isn’t much different, especially if you buy at Costco and already have a membership. They give me the cheapest, freshest fuel...pretty much a no brainer.
The problem with "studies" is that I can sway ANY study I want to show the results I want them to show. One of the biggest indicators is to look at who paid for the study. Often times you'll find that the company who paid for it was a big oil company themselves, so of course they paid to have the results swayed.
That's almost always the case with studies... or so I've found.
Oh, I agree completely...just look at big pharma and the unsafe shit they peddle! It’s all safe, just empty your pockets and trust us! Just wondering if there are any legit studies on top tier fuels that prove there is no benefit? My guess is that the truth is somewhere in the middle between the conspiracy theory and the claimed marketing. In my boosted application, I often test the fuels myself with real world logging and dashboard monitors to see if timing is pulled (pre-knock is sensed), and I know which fuel brands and stations that I have had issues with over the years. I won’t go into detail as this may differ from area to area from the folks I have talked to also doing this type of testing on the dyno and on the street. Nothing is better than real world logs on the street in my opinion. The reason for this, or at least part of it, is that “fresh” is just as important as top tier in most cases. Don’t go to that off the beaten path station that doesn’t have many customers per day. And like I explained above, the ultimate anti-knock solution for my boosted engine is ethanol (if your car’s fuel system can tolerate it and if your ECU and knock retard sensing system can take advantage of it). I know ethanol is corrosive and is the called the devil by many. I get it, I had a 300zx that had fuel injectors eaten by 10% ethanol fuels! But for my modern VW fuel system, it is an unbelievable fuel to mix with 93 octane and I have tons of real world logging to prove it works wonders.
I've "tested" 1 tank each of 87/89/93, no more than 1mpg change. Pointless to run anything other than "cheap" fuel. Also, consider the time these engines were designed, "fancy" fuel or ethanol blend regulations were much different when these Jeeps were produced.
If I remember correctly, California started the trend in 02/03 and the rest of the country started around 05-07(?), around the same time the JK was born.
Don't quote me, I'm going off terrible memory.
If I remember correctly, California started the trend in 02/03 and the rest of the country started around 05-07(?), around the same time the JK was born.
Don't quote me, I'm going off terrible memory.
To be honest I don't know enough about pump gas. Top Tier is a marketing ploy for sure, but that doesn't mean the gas is bad. It just means that they stick ethanol in it and it's all made to the same standard. I haven't heard of any issues with pump gas in over 10 years (before that was one station that was sucking water from their tank...). When I'm on a road trip I try to find ethanol free but I tend to stop where it's most convenient.
I wish pure gas was an nearby option for me. I would definitely run it in the TJ since it has an older fuel system...close to when they started the 10% ethanol mandate, or whatever it was. I wonder if there were any changes in the TJ fuel system components in regard to ethanol compatibility and longevity when the TJ went to direct ignition? If they did something midway, this would have been the time to do it.