iahphx

So the other day I'm refueling my rental car before returning it. I notice the station is selling E85 (generally, gasoline that's supposed to be 85% ethanol, but sometimes only 70% ethanol) for about 15% less than regular unleaded. I look at the gas cap on my car, and I see it's yellow and E85 certified, so I think "great -- what good luck," and I gas up for less.

Out of curiosity, I went online today to see what kind of gas mileage you get with E85. Basically, it's terrible: one study says you get 28% lower mpg.

http://www.cars.com/go/advice/Story....lAlt&story=e85

So, basically, I stiffed the next renter with a 28% higher fuel bill. Ouch.

Knowing what I know now, is it ethical to refuel with E85? It doesn't really seem so but, of course, how do I know I wasn't stiffed?

JMN57

Yes - it's ethical - whose to say you didn't get a tankful to start.

alphaod

I think it's ethical. I would have done the same.

marbe166

No you didn't since it is up to to the next renter if he/she fills up the car with petrol or E85. E85 is 25-30% cheaper (at least in Sweden) than petrol, so the mile cost is about the same whichever fuel you choose.

JMN57

I'll add - I believe it is pretty much a safe assumption that anyone filling up a rental car is going to put the cheapest grade gas into the car they can.

I was ticked off at a gas station attendant last month in Italy who pumped premium into my rental Cinquecento as I went to the men's room. He said they were out of regular and I said he should have said something.

alphaod

Well I actually found I get better mileage with premium (over a 3 week rental) even though the car said regular required (in the small print it said more power if premium is used).

I tested E85, regular, and premium over the same trips, and found premium to be the best value.

That said when I returned the car, I filled with the cheapest gas I could find, as long as it didn't harm the car.

iahphx

Well, it still seems a little "mean" to me, but I guess this is a new money-saving car rental tip. Is there an app that would direct folks to cheap E85 stations near airports? I have used gasbuddy to find gas stations near airports to refuel, but I don't recall seeing E85 stations listed there.

fairviewroad

I can't imagine for a moment why this wouldn't be ethical. It's an approved fuel for the vehicle, end of story.

Far better to fill up with E85 near the airport than to return it "full" after filling up with "normal" gas 30 miles away (because we've all had the experience of seeing the needle drop 5 miles after leaving the rental place with a "full" tank of gas, amiright?)

pinniped

Seems like fair game to me. The car is designed for E85, so if everybody uses E85 when they rent it, the per-mile cost all comes out similar to regular fuel.

I've never tested regular vs. premium in my own car. Do people get better mileage from premium because of the octane? Are you sure it wasn't because the standard grade was 10% ethanol whereas the premium was full strength? (I thought octane was more about power output, not fuel efficiency. If it isn't obvious from this post so far, I am not a mechanic. )

iahphx

Yup, as gas has gotten progressively more expensive the past decade, the prevalence of "not really full" rental cars has increased. It's darn annoying. And I'll admit to "returning the favor" when I get a "full tank" rental car that's short two gallons.

Of course, getting a tank full of E85 could be worse. It could easily cost you 15 bucks. That said, unless you're very familiar with the gas mileage on the vehicle, you might not notice you've been stiffed.

pinniped

Well, if this is of great concern to you, there are some options:

(1) If you're a National renter, you can simply not select Flexfuel cars. If you are Hertz or Avis, you can presumably get them to switch you to a different car if you find one in your stall. Or maybe something in your profile saying "No Flexfuel cars."

(2) You can check E85 availability near the airport you're renting from. If there is E85 easily available nearby, then you can pretty much assume your E85 rental car will be full of it. If there is no E85 within 50 miles of your location, then you can reasonably assume it has regular fuel in it and you aren't getting ripped off if you refill it with regular fuel.

(3) If you're in a city with *some* E85 options, but not near by the airport, then you can do two refueling stops if you've driven most of a full tank. Fill it mostly with E85 and then top off with regular fuel. It's these cities where I'd probably try to avoid an E85 car...I wouldn't want to hassle with two refueling stops, but it would gnaw at me that I didn't know if the guy before me did. (My own airport is an example: we have a few E85 stations around the KC area, but the stations near MCI don't sell it that I'm aware of.)

etch5895

Better than renting a car in some parts of southern Europe and the Middle East where they give you the car empty and tell you to bring it back empty. Who can work that just right? I'd bet the rental employees are siphoning out any fuel above the almost empty level and either selling it black market or putting it into their own cars. I'd much rather have the full option, even if I get stiffed a 1/2 gallon or so by the previous renter than scrambling to find a gas station when you leave the airport so the car doesn't die on the freeway and then potentially give back more gas than you got at the end.

FlyingUnderTheRadar

Filling it with E85 is paltry ... after a climbing trip we filled our rental car with all of the left over white gas.

DoggyDaddy

E85 is 85% gasoline and 15% Ethanol. Around here (NJ) this is the standard - by law.

As Ethane has less energy per pound than gasoline, E85 will give you poorer gas mileage than 100% gasoline. I don't know about premium gasoline - if it will give you better mileage or not.


DD

iahphx

Nope -- E85 is mostly ethanol, not oil.

http://www.fueleconomy.gov/feg/flextech.shtml

You may be confusing this with regular gasoline that's been blended with ethanol, typically 10%.