How fast does gas go bad in your tank?

[jhMalibu]

I'm a low miles person. On average a tank will last me 3+ weeks.

How fast does gas age in your tank? Should I be rethinking completely filling my tank when fueling? I am always in-city so a station is never far away.

Usually I add some MMO/LUCL mix I am trying to get through, but both my vehicles are on a Techron cycle right now.

Sorry if this is a silly question, but these threads about bad gas got me wondering if maybe I should try to increase my fillup frequency. I don't drive all the way to E, but usually fillup somewhere between 1/4 and E.

 

[sunfire]

I'd like to know the answer too. 10-11 gallons will last me 3+ weeks. I add the recommended amount of MMO. And I always drive to till the gas light turns ON. Which I understand can over heat the fuel pump. But I immediately fillup to full.

 

[danster]

At work we have a beater cube van that only hauls cardboard to the recycler. These are short in town trips about every 2 weeks in the summer and only one trip a month in the cold weather. It is a 1994 ford with the 390 cubic inch V8. We put less than 1000 miles on the van each year. I fill completely when I get fuel and refil when about at 1/4 tank. I want to get most of that "old gas" out. That is only about 3 times each year so one tank of gas might be 4+ months old before I add fresh fuel. We have not had any fuel related problems. I haven't bothered with any additives either although that would probably be a good idea given that the van might sit without being started for 30 days.

An important question for you: Are you using top-tier gasoline? If you are just quit worrying.

 

[mechjames]

Top Tier is good.

Fuel is usually good for about 3 months in my opinion before it starts going stale. This is from working in a small engine repair shop.

Cars have fuel filters and strainers on the fuel pump. Any varnishy stale gas shouldn't make it to the engine, and in a modern vehicle, if it starts to knock, the computer should change the timing to compensate.

Older vehicles with carburetors it might be an issue.

Check out all the davesfarm videos on youtubes with the cold starts. My guess is all the cars that get started a couple times each year are probably running on who knows how old gas.

 

[Trajan]

Spent six weeks in the hospital two years ago. The car didn't wasn't touched the entire time.

No problems at all.

 

[Carmudgeon]

I spent ten weeks out of town last year and had no problems with the fuel upon my return.

Chevron says up to one year is OK, under good conditions.

 

[Mamala Bay]

One year gas no thanks. Given I'd rather get my gas from a station that refills their tanks 1-2 times per week versus one that refills 1-2 months.

A while back Costco was selling fresh made gas and the price far lower than other stations because of the falling price of crude. The volume sold per day was insane. Lanes were full from 8 am till closing. You had motorist waiting in line 6:30 am in the morning getting there early or wait an hour for fill ups. Also fresh gas felt like it was spiked you could tell the difference. Gasoline aren't sold fresh to service stations are usually in storage for a couple of months or longer.

I know for a fact Chevron sells there lower grade gas to Tesoro.
The gas is still good or they wouldn't be able to sell it to the consumers. How old the gas is I don't know but makes me wonder why they would sell it off.

PS when Costco was not getting fresh fuel and the economy slowed the gas lanes at Costco look like a ghost town. At 8am you might see 5-10 motorist to fill their tanks up on the weekends. No waiting in long lines. Also because Costco's fuel storage is huge it made me wonder how often they were refilling their tanks. Actually I started having bad performance with their gas and I suspected others did to. From spike gas to stale gas Costco had poor performing gas and I'd rather spend the extra 15 cent on a station that refilled their fuel tanks once or twice a week. I suspected others did to. Until Costco volume of gas being sold was back to normal but not the insane fresh gas did I go back for fill ups.

 

[bigmike]

I fill up my truck about every 2 months. No problems. I use a little MMO occasionally and tried my first bottle of Regane on my last tank due to all the talk about it on other threads. Jury is still out as it might be March before I calculate what my MPG is!

 

[jhMalibu]

Seems like I was worrying about nothing.

 

[dwendt44]

I filled up my gas cans in the fall (08) and ran snowblower all season; not a lot of snow last winter.
Still ran good in March.
Put the rest in the cycle and used it up.

Most bulk tanks are only partially empty when new gas is added and mixed with the old stuff anyway.
A few months shouldn't make much difference.

 

[Gary Allan]

I bought a T-bird TC that sat for 7 years. SEVEN YEARS. Aside from some isopropyl alcohol to soak up the water, no problems with it. The guy who bought the thing was redlining it at the first corner and drove it through to VA without issue. He still drops me a line once in a while.

 

[JHZR2]

Originally Posted By: danster
At work we have a beater cube van that only hauls cardboard to the recycler. These are short in town trips about every 2 weeks in the summer and only one trip a month in the cold weather. It is a 1994 ford with the 390 cubic inch V8. We put less than 1000 miles on the van each year. I fill completely when I get fuel and refil when about at 1/4 tank. I want to get most of that "old gas" out. That is only about 3 times each year so one tank of gas might be 4+ months old before I add fresh fuel. We have not had any fuel related problems. I haven't bothered with any additives either although that would probably be a good idea given that the van might sit without being started for 30 days.

An important question for you: Are you using top-tier gasoline? If you are just quit worrying.


Ditto for my pickup, except I do use adds. Stabil for ethanol or 2-cycle oil. Sometimes FP.

 

[Mamala Bay]

Originally Posted By: danster
At work we have a beater cube van that only hauls cardboard to the recycler. These are short in town trips about every 2 weeks in the summer and only one trip a month in the cold weather. It is a 1994 ford with the 390 cubic inch V8. We put less than 1000 miles on the van each year. I fill completely when I get fuel and refil when about at 1/4 tank. I want to get most of that "old gas" out. That is only about 3 times each year so one tank of gas might be 4+ months old before I add fresh fuel. We have not had any fuel related problems. I haven't bothered with any additives either although that would probably be a good idea given that the van might sit without being started for 30 days.

An important question for you: Are you using top-tier gasoline? If you are just quit worrying.


Comparing driving a 1000 miles per year versus 12000 miles is not a good comparison.