What is the shelf life of gasoline?

[-]

Firestar-737@reddit

I used gasoline that was 10 years plus from underground tank it was good as new…

[-]

Polar_san_@reddit

As long as it stays dry, no humid place and chill degrees it should be ok for a long time. Probably a year or so

[-]

factory-worker@reddit

Soo... a bit off topic. I've been storing propane in my garage. Can anyone tell me how bad is that? It doesn't seem like a big deal.

[-]

hope-luminescence@reddit

Best to store outside. Especially if your garage has a furnace or water heater in it.

Propane can accumulate from a small leak, and can pool since it's heavier than air.... then, kaboom.

[-]

XOMartha@reddit

Would gasoline be okay sitting in a garage that gets up to 130 degrees?

[-]

hope-luminescence@reddit

I mean, if I had a better option I would store it somewhere else.

[-]

magicscholbus@reddit

Propane does not go bad. Store for a decade and use it, time is not its enemy.

[-]

Ok_Childhood2520@reddit

For a long-term you can use butanol. It can be used just by itself to replace gasoline. You can also make your own by fermentation

[-]

TSLARSX3@reddit

Get good metal Jerry cans with air tight caps.

[-]

Keep your gas in 5 gallon metal cans. When you gas up your truck put that in it and fill the cans. It never gets old like that. If you have more than the truck holds, oldest gas goes in the truck. Maybe you don't need to do this every time you gas the truck.

[-]

Gemcuttr98@reddit

I like metal cans for safety - good call, btw - but I won't store Gasoline with blended Ethanol in them. Because the Ethanol pulls water from humidity (or anywhere it can get it), unlined metal cans can rust through and leak. Also, rust particles can damage fuel systems and engines. BTDT.

I have not tried this (I use plastic cans), but I understand that metal tanks and cans can be coated internally with automotive fuel tank liquid liner. I've heard pros and cons about this - YMMV.

X2 on rotating the fuel supply! Forgetting to rotate supplies at least annually is a great way to wind up sitting in the dark with a warm beer! (Please don't ask me how I know!)

[-]

longhairedcountryboy@reddit

Yep, I have at least two places to get non ethanol. One has 93 the other 87.

93 is closer to me and usually costs less than the 87 that I have to drive farther to get so it's a no brainer which one I get.

[-]

Any-Application-8586@reddit

I got a ding on a metal can that made a pinhole because of the hot/cold cycle. Extra nice can that somebody paid $150 for too.

[-]

roberttheiii@reddit

Yes. A real air tight container helps it last longer.

[-]

NiceGuy737@reddit

If you want to store it pay more for gas with no ethanol. It sucks water into the gas.

Then add stabil.

[-]

eekay233@reddit

Unless you're in Canada. Ethanol free fuel is banned here.

[-]

Lakewoodss@reddit

You can get it at native reserves. Sometimes called boat gas.

[-]

DabblingInIt@reddit

Definitely not outright banned. Along with Marinas for boating there are scattered standard gas stations around that sell ethanol free gas. It will make a huge difference in small engines, especially with carburetors. It does seem like modern engines are tuned for it now. My older cars would get a solid increase in MPG when running ethanol free, but I didn't notice a difference the last time I ran a tank, if anything performance seemed down for some reason.

All the below is also true. It's a subsidy for corn farmers to keep our economy running. We grow a lot of corn, that's something we can produce, sell, and export which strengthens the US economy. Why do you think we tax cane sugar so highly and put corn-syrup in everything. Sacrificing the health and wellbeing of engines and people alike at the cost of a strong GDP and keeping the economy afloat.

[-]

Davisaurus_@reddit

Supreme doesn't have ethanol in Canada. That is why supreme pumps don't have a 'may contain ethanol' sticker.

[-]

eekay233@reddit

Starting in 2022 with a mandate to be fully compliant by the end of 2025 all fuel sold in Canada must be a minimum of 11% Ethanol. I think the only place you might find some if you're lucky is at marinas.

[-]

Davisaurus_@reddit

Is it the end of 2025?

You can find it at Irving. That is where I get my gas for 2 stroke engines. Irving won't put ethanol in for months after the deadline and say they forgot.

[-]

eekay233@reddit

In AB. Ain't no Irving's out this way. Although I miss Big Stop, is that still a thing?

When I was planning my fuel storage preps I checked a large number of the stations in my town. All ethanol. Which tracks cause AB produces so much of it.

[-]

Ingelwood@reddit

You will be pleased to note that Big Stops are still here, but owned by Circle K now. Still have great convenience stores and restaurants. Huge sandwiches are still sold, last I was in one.

[-]

eekay233@reddit

I was introduced to adult food by means of the club sandwich as a young lad driving from Labrador to the island via Sydney for summer vacations. Very fond of those restaurants.

[-]

Ingelwood@reddit

The Club is my all-time favourite! Has one before Christmas.

[-]

Marklar0@reddit

At least in Ontario, supreme does have ethanol and its really hard to find any gas that doesnt, as the stuff from the gas station is not allowed to be ethanol free

[-]

ottawamale@reddit

If you happen to be near a reserve, many have ethanol free gasoline, and for much less per litre. I take a trip up to Bala now and then to fill a few jugs for lawnmower etc, lasts a long time.

[-]

jasonc122@reddit

Nope you just have to shop around

[-]

Additional_Ad5671@reddit

Banned ?? Why ?

[-]

coatingtonburlfactry@reddit

Wait. What about boaters. You definitely don't want to use gasoline with ethanol in marine engines. Is ethanol free fuel available only in marinas?

[-]

wykedtexas@reddit

Buccees sells ethanol free

[-]

Noremac55@reddit

As a Californian forced to buy ethanol gas, they claim its for the environment. In reality, it creates an artificial market so that our gas is more expensive. Yay paying more for a shittier product.

[-]

dittybopper_05H@reddit

It's also a subsidy for corn farmers.

[-]

SarevokAnchevBhaal@reddit

It's also a way for gas companies to cheap out. Pure ethanol is 106 octane, and gasoline gets a massive octane boost from adding ethanol, but like 95% of that benefit comes in the first 10% so your 87 octane gasoline is more like 84, but with 10% ethanol to bump it to 87. Your 93 is probably 87 before the ethanol, ans the ethanol is the only reason it passes standards for 93.

[-]

schizosi@reddit

You’re correct, it was never a conspiracy to raise gas prices, was always a way to keep corn farmers afloat (and to decrease the average CO2 footprint of gas cars, but it’s not particularly effective at that)

[-]

eekay233@reddit

Could never find a full explanation but it was a ruling of the highest court.

[-]

jprefect@reddit

Corn subsidies. A bribe to red states, frankly. The Western wing of Nixon's "Southern Strategy"

[-]

neverless43@reddit

the explanation is money, ethanol is clean if it came from nothing, but the growing and harvesting and conversion of the corn creates more carbon than just burning normal gas would. but then farmers are powerful and it makes them more money

[-]

IndependentTeacher24@reddit

Not to mention all the synthetic fertilizers keep the chemical industry going as well.

[-]

Lopsided-Total-5560@reddit

That’s been my opinion all along! People look at me with the “deer in the headlights “ look when I explain it. Most don’t realize how much diesel is burned to: spray field with roundup (no till), drill corn, spray corn and/or cultivate, combine corn, transport to silo or dryer, transport to grain elevator, transport to refinery. Before it’s even harvested, it’s at least 4 passes over the field and that’s no till. Add two more passes if conventional tillage.

[-]

TN_UK@reddit

Ymmv but my ethanol free gas has lasted over 13 months. I bought 10 gallons last spring to mow and to have for my generator come winter.

I've been using it all spring to mow again.

I've had it in my garage in the Midwest. 40-90 degrees throughout the year

[-]

AlotaFajita@reddit

You might be using 13 month old gas but the octane has decreased and it’s not be great for the engines.

I’m using last fall’s gas in my old chainsaw I use to cut stumps low to dirt and I cringe when I use that gas, but the saw is 20 years old and I have 3 more so it’s sacrificial.

[-]

EverVigilant1@reddit

Yeah. Good plan. Or just dump it into your car.

[-]

dittybopper_05H@reddit

"Sacrificial Chainsaw" would be a good band name.

[-]

I_Want_A_Ribeye@reddit

Tru fuel is great if it’s a tool that you aren’t using all the time

[-]

tianavitoli@reddit

i stored premium california pump gas with pri-g added for 2 years. no problem, none.

[-]

recyclingloom@reddit

1 year if stored properly and you use the correct amount of gasoline stabilizer/addictives.

[-]

Civil-Barracuda-989@reddit

I’ve has ethanol, free fuel stabilized with sea foam last me for two years. It ran my lawn mower and generator just fine. I couldn’t tell it wasn’t fresh.

[-]

lostscause@reddit

Gas doesnt just go bad, it degrades

Example: no ethanol 92 octane

it starts out as 92 octane and loses a few each month. till 6 months from now you have you have 86 octane gas. You can extend this by adding stabil when first storing it and a bottle of octane boost when you use it.

Best to cycle threw it if you can. But careful , the stabil will make your car smoke a bit if you try to use it up that way.

I ran 2 year old gas in an old gen set , would i run it in my BMW no ..

[-]

drbooom@reddit

There are numerous cases of sealed 55 gallon drums of leaded gasoline being found in Old mines in the southwest. As long as they haven't rusted through, and still contain pressure, the gas is still usable even when the fill date is in the 1950s. Those people use it in carbureted cars, not fuel injected engines. An acquaintance of mine found a 55 gallon drum of aviation fuel in Alaska, 110 octane. It dated from world war II. He had it analyzed and it came back as over a hundred octane, he said he did run it through a filter and that the filter picked up a lot of yellow particulates. It ran in his 2018 fuel injected pickup.

It's a combination of oxygen and water that results in gasoline going bad. (?) Obviously ethanol- containing fuels are going to have a much bigger issue.

[-]

Internal-Eye-5804@reddit

Stored properly with a good stabilizer, it can last much longer than most people think. Last summer I used gas (non-ethanol) that I've had stored in a sealed drum with PRI-G stabilizer......since 2017. I'm always using 2-3 year old gas stored this way, but this drum somehow got lost in the shuffle. It smelled fine and burned fine in all my equipment including lawn tractor, chainsaws, log splitter, hedge trimmer, generators, weed whacker, etc. Not a miss or stutter from any of them. I'm using the last of it up now in my mower and other yard equipment.

[-]

DeafHeretic@reddit

I store gas in my shop for years - in 5 gallon safety cans, in a 55 gal drum (with Pri-G added), and in various equipment. I have no issues with gasoline degrading.

I have a pickup that has sat without driving it for over a year. Yesterday I started it to move it - no problems.

Some of the gas has been sitting for well over a year - the gas in the drum for several years.

The only time I have ever had issues with gasoline was when I got gas from a station that had crap gas (mostly it had water in the gas) and that was an immediate issue as the engine had problems within a few miles - once I had issues with the fresh gasoline freezing because of water in it.

[-]

gizmozed@reddit

I only buy ethanol-free gas for storage. I never use stabil which I'm skeptical actually does anything.

I have used gas that is at least 2 years old with no issues. I will say that the volume of gas in my 5-gal plastic gas cans definitely diminished 10-15%, (volatiles outgassed) but that had no effect on it's usefulness that I could detect. I've used this old gas in small engines like lawnmowers and ice cars.

I've used diesel that was even older. No problem.

I say this because I routinely see claims that gas will only last 6 months, 12 months, whatever. On what basis these claims are made I have no idea. I'm making my claim based on actual experience.

[-]

Initial_Patient_9096@reddit

I thing the highest grade in an air tight container can last 3 or more years.

[-]

Jake_Break@reddit

Premium with stabilizer kept in cool, dark storage, has been good for up to 3 years for me. Works fine in my generator and Honda at least.

[-]

ihuntN00bs911@reddit

You can buy special fuel at Home Depot, but I would look into making fuel by pressure cooking plastics then cooling

[-]

hope-luminescence@reddit

... Have you actually tested doing this and producing a fuel that will run commerical ICEs? In any significant quantity?

[-]

ihuntN00bs911@reddit

THIS SELF SUFFICIENT FAMILY MAKES THEIR OWN FUEL FROM PLASTIC! The Gipsy Journey

[-]

tkb072003@reddit

As a former mechanic, an avid researcher, completing fuel related education, and a lifelong machine enthusiast your best way to save gasoline is in a sealed tank filled 90%+. Water is your number one enemy.

You will get any well maintained machine to run on 2 year old 10-15% ethanol fuel with no additives using that method. More than you can store - that machine will eat it all up.

Non-Oxygenated Fuel will store that long or longer without long term usage effects.

Don’t buy DOT rated gas cans as they all leak, spill, and allow water vapor in. Buy “Utility Jugs” or VP Racing Cans in the 5 gallon size and fill it to just under the vent. Tighten the caps to hand tight and you are done. Cycle out your cans every six months and whenever something bad happens you have fuel that is useable for 1.5-2 years.

[-]

hoardac@reddit

I buy ethanol free and add stabil. I rotate the cans every 2 years with no issues. Just attach an aluminum tag to the cans with the month and year to use them up. I have run them in my chipper and chainsaws with no issues but most usually goes into the car and truck.

[-]

IdealDesperate2732@reddit

Rule of thumb is about a year. Storage conditions will affect this considerably.

[-]

ResponsibleBank1387@reddit

I buy the cheap ethanol gas. It’s in a hundred gallon tank. I add a cup of water. Every week the first gallon off the bottom is mostly water. You can tell as it comes out. Water on the bottom is used in the weed spray, the gas is ready to use.

[-]

Ok-Satisfaction330@reddit

In air tight NATO Jerry cans I use gas 4 years old. I have a long rotation for mowers and blowers. I add stabilizer when filled.

[-]

RiffRaff028@reddit

Buying ethanol-free and adding a preservative I've gone as long as two years and the gasoline was still fine. That being said, I would recommend an annual rotation just to be on the safe side.

[-]

GravySeal45@reddit

the secret is AIR TIGHT containers, dark dry and air tight with as little air as poss inside the container.

Ethanol free and stabilizer exponentially raises the shelf life.

[-]

WhereDidAllTheSnowGo@reddit

Depends on engine

Model T will run on 50yo gas, Honda generator requires new

[-]

SharkStomper@reddit

I mean, I use gas in my riding lawn mower in March that's been sitting since at least September with no issues. So I'm dubious of the 6 months thing.

[-]

KingoftheNordMN@reddit

My snowblower died under similar circumstances

[-]

SharkStomper@reddit

I like to live on the edge. Same as I have the last 40 years of mowing yards. Sorry about your snowblower.

[-]

KingoftheNordMN@reddit

She came back- $100 later:)

[-]

Fun-Chemistry-4629@reddit

You're talking about, I assume, you didn't need your lawnmower for winter.

So in your freezing or near freezing climate, the humidity is very low, or non existent.

So yeah, the humidity didn't enter the gasoline.

In Florida, a gas can is "fire gas" after 2-3 months.

I wouldn't put gas that's been sitting a month in my car, but lawnmower or whatever Honda motor is probably fine because you can drain the carb.

I don't know if I'm the only one, but I won't even use a small gas station in the country. Buddy I wanna see a Wawa with 35 customers so I know it's fresh

[-]

MintedMokoko@reddit

There’s such a massive difference between your lawn mower and a vehicle.

Your modern day vehicle will miss fire and knock like crazy on 6 month or older gasoline. This will lead to premature engine failure after continuous use.

Your lawn mower, which could be run on piss and vinegar, couldn’t care less about unstable fuel.

[-]

SharkStomper@reddit

I didn't realize a generator is considered a vehicle. :Themoreyouknowmeme:

[-]

Eazy12345678@reddit

modern cars will use computer to adjust for bad gas

[-]

stackingnoob@reddit

I guess OP wants to know if it can be used in a generator moreso than a vehicle. I personally have not tried using old gasoline in a generator. Hopefully someone who has can comment.

[-]

EverbodyHatesHugo@reddit

If The Walking Dead has taught me anything, it’s that gasoline lasts years, whether it’s stored in a proper container or siphoned out of a rusty vehicle.

[-]

Paranormal_Lemon@reddit

It varies based on temperature, humidity, container type (how easily it vents) etc

[-]

waffy88@reddit

I’ve used gas properly cared for that was three years old. There are tricks.

[-]

Many-Health-1673@reddit

Ethanol free gas in an air tight container with Stabil or PRI-G should last at least 24 months if kept in a moderate environment. 5 years if kept in a controlled environment without large temperature swings.

[-]

Short-University1645@reddit

I use ethanol free, and rotate them over a year with mowers and generators. I try to keep 50 gallons at any given time. I used a 3 year old gas can for my Honda generator and it ran fine this past summer. Use blue tape to date the cans

[-]

RallyX26@reddit

I've had ethanol free gas last 3 years in my generator start up on the first pull and run flawlessly. Ethanol mixes (regular pump gas) are pretty useless after a few months.

[-]

Jaicobb@reddit

Years.

Based on personal experience. If you avoid the gasoline with ethanol mix, even 10%, that is. Just a small amount of ethanol reduces the shelf life considerably. Add some fuel stabilizer for good measure, but that stuff works best with ethanol blends because ethanol is so bad. It works by absorbing the water.

Store it out of sunlight. The cooler the better.

[-]

Federal_Difficulty@reddit

Yep, I’ve used 2+ year old gas in small engines and an old beater car. No ethanol, stabil added at start. I didn’t do this then, but if I were using old gas like that again I think I’d add some isopropyl when using it.

[-]

IrishSetterPuppy@reddit

Even E10-E15 lasts years. When I sold my Z28 a few months ago I think the gas that was in it was from 2015. It started right up and ran great even in a 12.5:1 compression engine. No additives or anything was in it, just pump gas.

[-]

Jaicobb@reddit

Glad it worked for you. I recommend against E gas in almost every situation.

[-]

Barky_Bark@reddit

This. The general advice is 6 months but I’ve personally burned 2 1/2 year old has. After Covid shut my business down, we didn’t get any new gas from sept ‘19- may ‘22. 150 gallons still burned in an ATV and modern outboards.

[-]

Eazy12345678@reddit

i rarely drive. i have had gas in my car for over 6 months with no issues. but my car is kept in a garage and temps are good. 50-90F

[-]

hope-luminescence@reddit

Was this with fuel stabilizer or without?

[-]

Heck_Spawn@reddit

Smell it. If it smells like varnish, use it to start a burn pile. That's all it's good for then...

[-]

Select_Asbestos9680@reddit

I have some garage art that hasn't had fresh fuel in 10 years. It will still start and move on that fuel. I move it outside once a year to clean.

It doesn't run smooth, nor does it like to rev, but it does run. This is E10 pump gas.

[-]

LegallyInsane1983@reddit

Get good metal cans from harbor freight. Replace the pour spouts and caps. Get ethanol free gas and add stabilizer. I have had it last a year. I used it before a year passed.

[-]

ihaveadogalso2@reddit

I have 15 gallons stored in my she that I rotate throughout the year. I've let one of the 5 gal cans sit for well over a year and have had zero issues with it. I just use 87 pump gas with 10% ethanol, i put in a nice dose of stabil and call it a day.

[-]

xxmadshark33xx@reddit

From my understanding ethanol free/ rec fuel with fuel stabilizer will last the longest. The second-best option would be higher octane fuel with stabilizer. If properly stored and treated they should both last a couple of years.

[-]

Temporary_Advice621@reddit

I add stabil and have had no issues for a whole year. But I also only be ethanol free gas to store away for my small engines.

[-]

NewEnglandPrepper3@reddit

Add stabil to increase shelf life.

[-]

Foodforrealpeople@reddit

short of the "fuel only lasts 6 months" and "you can extend it's life by a few months if you add a fuel stabilizer" what i have found over the last few years of periodic research is as follows. The older the fuel is the great the chance of increased maintenance due to particulate build up and potential clogging of fuel filters/injectors.

On an anecdotal side: i used to work for a fuel company and we had many contracts where we checked fuel storage tanks for emergency generators (both diesel and gasoline) on an annual basis. if they were below 90% we topped them off otherwise it was next year when we checked them again. Due to being in a fairly mild climate there are very few power outages so the4 only use sometimes for years is the standard start up checks they do.

A LOT of farmers fill tanks at the end of harvest (when they have money) and run that fuel (diesel and gas)all the following year in their tractors, trucks and cars. We also had a security company that had a gasoline 10,0000 gallon storage tank for their "fleet" of cars.. we filled it every other year

[-]

CaptainJay313@reddit

gasoline is chemically complex and designed to vaporize at different temperatures. (it needs to be in a gas state to burn) the longer it sits, the more lower temperature (below ~110°F) parts evaporate and it becomes more difficult to get it to combust.

summer gas and winter gas are also different - winter gas evaporates at lower temperatures and therefore would have a shorter shelf life in higher ambient temperatures.

[-]

Moist-Golf-8339@reddit

My stored gasoline rotates from storage, to snowblower, to mixed for chainsaws. My saws are running last fall's gasoline now. I had added some stabil and it was non-oxygenated and ethanol-free.

[-]

davidm2232@reddit

You are totally fine for a year with no stabilizer as long as it is non-ethanol. 2-3 years with stabilizer. I've run 5 year old untreated gas in my Jeep. Less power and it will detonate under load. But it will run.

[-]

KinkyChieftanDaddy@reddit

Use stabilizer and you'll get up to 12 months.

[-]

Hot_Annual6360@reddit

Using butane gas lasts for decades, now answering your question, in company generators (emergency generators) normally diesel, they last for years, I say this because in the last inspection of the equipment where I work, the diesel tank has been there for more than 3 years, it starts and works perfectly)

[-]

plowdog46150@reddit

Go get 100 LL aka. Avgas from the airport it will last a year or more if stored properly. but what ever you put it in it will run hot because it's over 100 octane. I ran it in my rav 4 I was getting an extra 50 miles out of a tank and it's crazy expensive

[-]

Odd_Cost_8495@reddit

Add stabil to your gas. I cycle through my 5 gallon jugs once a year. Never have a problem. Stabil claims to keep gas fresh for two years from the date you open the stabil. I don’t push it to two years but never had an issue with using it a year later. I add the 5 gallons to my car and top off with fresh gas.

[-]

Background_Ice_7568@reddit

I have two 5 gallon tanks with stabil, and I put expiration dates on them for 6 months out; if they aren't empty by then, I will dump the rest into a half full tank of gas in my car, and renew them. They're offset by 3 months, so I always have a full tank that's never more than halfway through it's "lifespan".

We don't have any great ethanol-free stations near me, so it's the best I can do. Trufuel is just too expensive for me to consider it to be honest.

[-]

True_Way2663@reddit

Yep I use Stabil as well and refresh the container every year

[-]

Dangerous_Echidna229@reddit

My gas was fine after two years in sealed metal cans with Sta-Bil.

[-]

TheThingsIWantToSay@reddit

I have a lawn mower, if the gas was in it with stabilizer over winter it would start up, gas without stabilizer would not and I have to clean the carburetor. But I could use the same year old gas.

I put stabilizer and have used 1-2 year old gas in lawn mower and generator as needed.

Would consider propane tanks and generator for the future, waiting for what I have to break… before doing that or having extra cash that I don’t need for kids/family/vacation.

[-]

lazyoldsailor@reddit

Gas is ruined in two ways. First, when it gets hot, called thermal decomposition. The hotter it gets the faster it breaks down. Best protection is to keep gas somewhere cool.

The second is water absorption. Usually humidity gets into a tank, moisture gets in, and the gas goes bad. Best protection is to keep the tank full with little space for air. Otherwise the air will expand and contract daily with temperature changes bringing in humidity with each ‘breath’.

[-]

Whenwhateverworks@reddit

We started my grandfathers old chainsaw with 18 plus year old petrol in it, it ran fine.

[-]

Nojka69420@reddit

Store diesel, lasts forever if stored properly

[-]

Unlikely-Ad3659@reddit

I used to buy and restore old cars, I have run some that had 10 year old pre ethanol petrol ( not going to call a liquid, gas) in them.

Not sure what the quality was like,I imagine significant degradation, and fuel injection would hate it, but it can last longer than we think, but I would always mix it 50/50 with new fuel as soon as I could.

The breakers yard I used to work at all the petrol from old cars was just poured into a big barrel via a filter and used in whatever car needed it with no issues, my guess the average age of that fuel was 3 years old.

[-]

cobrakai15@reddit

I just put some 6 or 7 month old gas that was under my porch in a can with no stopper in my mower, ran fine. You can put sta-bil in it. Gas is mixed differently by season so that may be something to think about.

[-]

liswat@reddit

I can do a year in metal cans, with stabilizer, just regular old gas.

[-]

Lethalmouse1@reddit

In ideal conditions? I'd give it about 2 years.

Ethical free + stabil + good container etc.

Under less than ideal conditions and any Murphy laws, 6 months - 1 year?

[-]

Ryan_e3p@reddit

You can stabilize it with commercial products that can make it 'safe' to use up to 2 years. I've run stabilized fuel in my car that was almost a year old, no issues.

That being said, I've had fuel (regular fuel from the pump, with 10% ethanol) without stabilizers sitting in a land tiller for 4 years, and it fired up on the first pull with no problems.

I suspect that more "dumb" devices like lawn mowers, tractors, and other similar equipment will be more or less fine. Cars, with complex emissions sensors, will likely light up like a christmas tree.

[-]

Additional_Ad5671@reddit

Problem with the “dumb” devices though is that the ethanol fuel gums up the carburetors. Not the end of the world, but annoying.

[-]

Keppadonna@reddit

Based on my experience over two decades and plenty of internet affirmation, ethanol free fuel treated with stabil will last one year no problem. What’s the max? No idea. Would I trust eighteen month old treated fuel? Yeah.

[-]

Windhawker@reddit

Stored in a 5 gallon container, add Stabil, put a date on it. Rotate every 6 months by using the 6 month old gas in your car and getting a fresh fill up of 5 gallons, add Stabil … repeat

[-]

Jacklebait@reddit

I've posted this response before when this question comes up. As a former military fuels lab technician we didn't even bother worrying about gasoline until it hit a year or more. This is standard gasoline you get from any gas station. 1 year and you're fine, after one year it's best to mix it with newer gas. A simple test is to pour a small amount into a shallow container, light a match and drag it over the top above the liquid, if it lights it's still viable.

Just be careful using the match, we have a device that does it (Flashpoint tester) so our fingers don't get burned.

Take this as you will, everyone else I'm sure will dispute this, but if the military does it with millions of gallons just fine, you can also.

[-]

-zero-below-@reddit

I have an old generator that I mostly replaced with other stuff and didn’t use for a few years.

Then I decided to fire it up. There was still gas in it, oil level was fine. It fired right up (pull start) and I used it for a week. It sat again for a few years, and the next time it started right up again.

I think it helps to not keep opening the cap, leave the tank full (less air = less water). And crappy generators generally have pretty low fuel requirements.

[-]

Specialist_Loan8666@reddit

I have 5 gallon cans and I put the correct amount of stabil in each can prior to pumping gas into them. Every summer I use them in mower and two 2019 /2020 vehicles and the gas is fine. So a year with stabil it’s fine. Might be able to get 18 months. Just rotate it

[-]

ThorAlex87@reddit

Tl:dr: It depends, but is usually fine at 6 months...

In my experience it will depend on the engine you use it in, (some are more picky than others), how it's stored, what kind of gas it is, luck and whatever. Ethanol free high octane I've used up to a couple of years old and never really had problems with. Low octane with ethanol I've used a year old but that is pushing it, one generator I sometimes use is really picky and won't start on gas more than 3-6 monts old (not mine, I'd never run ethanol in a generator, i just have to fix this one when it won't work). Storing gas in good quality containers in a cool and dark place will make it last longer, but I'm unsure exactly how much. Old fuel from a can usually won't damage anything but sitting in the engine while getting old will make a mess. Any engine not used regularly I'll run dry before storage, saves the carb from getting gummed up.

In Europe we can buy a special clean gas in cans for lawnmowers and chainsaws and such that will last significantly longer but is also a lot more expensive. I could not find what it's called in English, maybe som brits on here will know? Officialy it has a shelf life of a year or something like that, but I used up a can a few years ago that had sat half full for at least 10 years and it worked perfectly fine...

I try to rotate my supply so it never gets too old, and always buy the high octane ethanol free stuff. I don't keep too much of an emergency supply thought so I usually go trough it in a year or less with normal use and knowing my equipment that gives me a years margin should I for some reason use less. I should probably keep more for emergensies but I'm already way past my comfort zone (and the legal limit) for amount of flammable stuff stored in the garage so I'll have to build a fuel depot of some sort first...

With the availability of dual fuel generators now, if I where to buy new I'd just buy that and store propane tanks instead, those last basically forever.

[-]

hope-luminescence@reddit

It gradually degrades, and degradation depends on conditions. (high quality ethanol free gas, in very well sealed metal gas cans, 100 percent full, with the ambient temperature being constant and not overly hot, is the best case.

Sometimes really old poor fuel will run something way longer than 6 months... or it won't, or run really rough which is bad for engines... or bits of varnish will plug something and you'll have to fix it -- hope you know how and have tools.

[-]

ThatRedheadID@reddit

Seems I read an article in Hot Rod magazine that said non-ethanol gas when stored in a cool dark place in a full container should be good for a couple of years. One easy option would be race gas in a can from a company like VP Racing. A 5 gallon can will set you back $99. Optionally, you could top off your brand new plastic fuel jug with some stabilizer and non-ethanol gasoline for considerably less money.

[-]

NickMeAnotherTime@reddit

I used a two year old bottle of gas to power my chainsaw. It did have a stabilizer in it though. The chainsaw worked just fine.

[-]

MechaMonsterMK_II@reddit

Glad you asked this, I was thinking the same thing.

[-]

SetNo8186@reddit

I've heard 90 days, and even 2 stroke mix will clog up a weed eater in that time and it will not start. Especially any kind of gasahol, which will oxidize the plastic fuel lines and distort diaphragms. Some makers say lawn tools will tolerate it, but none recommend E15 whatsoever - E10 is the culprit we fact that does mess up equipment.

This is why it's recommended to drain the tank and run the system until it uses every drop and shuts down. When I do that I get quick and easy restarts with new fresh fuel, when i ignore it I get the Weedeater from Hell that will not start even tho it ran just 4 weeks earlier.

I just asked the local lawnmower repair guy if he worked on two stroke weed eaters and without any hesitation he said NO. Most of this is because gas is now contaminated with up to 50 different ingredients - each metro has it's own recipe, and everything in it comes out the tailpipe for us to breathe.

Fuel with no alcohol still requires additives like Stabil to prevent the oxidation of the hydrocarbon chains and rarely stores well, and should be cycled out of the stream and used. This is why so many are moving to duel fuel generators to run on propane - which might reduce the output slightly but do not create gums, contamination, or damage polymer parts.

[-]

AdditionalAd9794@reddit

It depends on the vehicle, I have an old dodge ram, it had like 18 month old fuel in it, it backfired and misfired under heavy load, but cruising st steady speeds, without hard acceleration, it was fine.

That said i know a guy who put old fuel in a brand new F-150, I suspect the fuel also had two stroke oil, dudes and idiot. He ended up with a $4,000 repair bill.

Generally speaking I'd say 6 months is fine for most vehicles outside high performance, all year or more, I wouldn't put it in any newer vehicle

[-]

Immortal-one@reddit

Add fuel stabilizer. Stabil says that their product, as used, will keep gas good for 2 years.

I also did a little experiment a while ago. I filled half of a clean, dry 2 liter soda bottle with gas and left it alone. In about 4months there was water settling to the bottom of the bottle. That stuff definitely won't run in a generator.

[-]

ryanmercer@reddit

3-6 months, typically, before it starts to get to a point where anything more than a mower is going to get gummed up by it without stabilizers.

I usually cut grass for the last time around October, leave gas in the mower and gas can until late April and cut grass wth it again, but that's a mower. It doesn't mind much.

I had some in my t100 tank for almost 2 years without it having been driven, it did not want to stay running until I severely diluted what was in the tank and even then ran not so great until I got it to almost empty and filled it up again.

On the other hand, you'll see Vice Grip Garage, Junkyard Digs, Pole Barn Garage, etc on YouTube start up something with a decade old fuel in it occasionally, but again very very very rough and not so great for whatever it is running through.

[-]

silasmoeckel@reddit

Octane goes down and junk particulates out.

So your clogging filters and causing issues in some engines.

Now a modern car/truck dilute that down and let the computer deal with any knocking.

That's pump gas with ethanol. The degradation starts getting noticeable after 6 months (the smell changes) us a treatment to extend that it's cheap insurance.