E85 instead of gasline anti-freeze


Alcohol causes water to mix with gas, right? So if I put a small amount of E85 in my tank instead of the $1.50 an 8oz bottle stuff off the shelf I should get the same result cheaper. Am I right or barking up the wrong cornstalk?


E85 will absorb any water in your gas tank, usually caused by condensation. Give it a try, but put in more than 8 ounces!


why not isopropal alcohol from the drug store, about $1 per quart?


where can you buy e85? how much is it going to cost per gallon? if you buy a gallon of e 85 how much are you going to save money? i don’t think so.

ethanol is a grain alchohol. part of this IS water. i don’t know how the mix goes, but why not just buy gas at a reputable, clean, gas station that filters their gas, and has a good reputation for not having water in the gas? and keep your tank full, so it wont condensate and create its own water.


If you live in a cold city and park overnigth in an underground heated garage, and then park at work outside in the cold, you will get condensation from the heat/cool cyle. The best defense is to keep the tank full, and add a little alcohol every tankful.

Water in the gas is normally not caused by bad gas station fuel tanks.


There is a station near my home that has E85. Last I checked it was about $3.50 a gallon. Divide by 8 and one pint is less than 50 cents. I do keep the tank full, and have personally never experienced a freeze-up. We get a lot of around freezing temps and humid weather, and a 30 gallon tank has a lot of surface area so I put a bottle in once or twice every winter. Granted the cost savings is minimal, but it would be easy to put in a $1 worth of E85 when I am already filling up at the next pump. I like the isopropyl alcohol idea, if I bought the 99% stuff there would be no water in the alcohol I am dumping in. Does anyone know if isopropyl alcohol will damage a non-E85 fuel system?


The isopropanol in the drug store is probably USP grade and much higher purity than you need to burn in your car. I don’t recall if it is 100% alcohol or 70%. If the latter, it already has lots of water in it so stay away. E85 should work great. Dry Gas as it was often called, came in ethanol and isopropanol varieties, IIRC.


i am NOT a chemist. but there is a difference between isopropyl and ethanol alcohol.

i believe that they have different chemical properties. i personally wouldn’t trust the difference in the fuel system, and gaskets myself.

if you try it, let everyone know how it works out in the long run.


The problem with rubbing alcohol is that it already contains anywhere from 9 to 50 percent water. To act as an effective co-solvent to make condensation dissolve in gasoline, it has to be dry to begin with. Yes, there is a difference between isopropanol and ethanol. Ethanol will get you drunk and make you wish you were dead the next day. Methanol will make you actually be dead the next day. Isopropanol will likely put you in the emergency room. T-butanol is not only poisonous but it also freezes at room temperature. The higher the molecular weight, the less water soluble they tend to be, cholesterol for example.

If it ends with the suffix “ol”, it is an alcohol. Ethyl alcohol is ethanol, calling it ethanol alcohol is like saying “ATM machine, PIN number, UPC code, and,and etc.” All are grammatical redundancies.


Yes, and no and Why?

Yes. It will absorb water.

No. It is not as effective. The type of alcohol is not as effective, it is only partly alcohol so you are going to need to use more. Remember that E85 has less energy than gasoline so it will lower your mileage a little as well.

Why? Few drivers ever have a problem with it. The usual additive package will handle the usual condensation in the tank of a modern car. The only time most drivers will face that problem is when there is a mechanical issue and then at little E-85 is not going to fix it.

The use of a dry gas product as a prevention is a waste of time and money.


true. I’ve driven for more than 30 years, never used any additives, never had to.


“The use of a dry gas product as a prevention is a waste of time and money.”

Absolutely correct. Plain old fresh gasoline will handle all normal moisture situations. I am not going to waste any more bytes on this one.


Ethanol doesn’t mix with water. As matter of fact ethanol will cause water to phase seperate out of gasoline. So you end up with a layer of gasoline, water, and ethanol. And it’s this layer of water that can freeze. This is one of the reasons why the concentration of ethanol is dropped from 10% to 7%-8% in the cold winter months to prevent phase seperation in the gasoline.

Isopropyl alcohol on the otherhand does aborb water. And will hold it so it doesn’t freeze and so it can be carried off into the engine to be burned.



Is your car a flex fuel vehicle? If it isn’t, E-85 could damage it.


Why? Few drivers ever have a problem with it.

It’s NOT that uncommon…at least in the NE. Happened to me a couple of times in my 30+ years of driving. But usually only on very very cold days (-10) or lower. When a cold spell is comming I usually don’t let my tank get below 1/2 full.


Ethanol doesn’t mix with water. As matter of fact ethanol will cause water to phase seperate out of gasoline.

This is incorrect. Ethanol is miscible with water, and very soluable (if it isn’t miscible) in gasolene. Also, if what you suggest actually happened then people using ethanol based dry gas (which is a good percentage) would be having problems.


It happened to my boyfriend one night in college. It was in Potsdam, NY, which is 2.5 hours north of Syracuse, on a very cold (about -20F) night. A lot of other students I knew had trouble with condensation freezing at one time or another. You just couldn’t let your gas tank get below half full, like MikeInNH said.

Living in Syracuse now where it’s rarely below 0 (feels like a mild winter compared to college!), I still stick by the same rule and I haven’t had a problem.


i dont think the percentage of ethanol drops in the winter. we haul the same stuff year 'round. the cars need the same octane no matter what the season is.