We have two Elantras. My wife's 2 liter 06 GLS automatic has averaged 33 mpg at 15K and 80K miles. That's averaged across 3 consecutive tanks - over 1000 miles divided by the sum of the 3 fillups. Driving is 70% highway, 20% rural, and 10% city. All terrain is hilly in central NH. I am thrilled with her mileage.

My 2011 1.8 liter is a disappointment so far. It's only been one full tank so calculation is very inexact, but the trip odometer also confirms 29-31 mpg. That is the same driving mix as the '06 Elantra. Resetting the trip computer when I get on the interstate reports an average of 32mpg on cruise-control at 65 for 20 miles. Lots of hills on the highway - it drops as low as 4th gear trying to hold speed on some of them. Then the mileage tanks (no pun) to low-mid 20s during 6 miles of hill country to and from the hwy.

My suspicion is that on flat roads it might be good for upper 30s, but the tall gearing and small engine is a bad combination when it must contend with hill after hill. I know that it is not broken in, but i don't believe that you see a 20% boost in economy after break-in.

Mileage aside, I love the new Elantra. All 06 features were mediocre - ride, radio, power, bodywork - although fuel economy, price, and reliability are exceptional. The '11 addresses all of those shortcomings - but the jury is still out on real fuel economy.

 

Kermujian,
I wish i got 32mpg on my first tank. I live on very flat Long Island and I drive very early in the morning, so I don't hit traffic. I do get some stop and go on the way home, but then go around 60 for the longest part. I only got 19 miles per gallon. I have 1400 miles on now, so on the 4th fill, i have been extremely diligent not to go to fast, to coast, to drive smoothly, and not to rev over 2,000 rpms. I am now getting 28 mpg. I find this strange, since the combined mileages should be over 30 mpg. I have complained to Hyundai. I am waiting to see what happens. I had a 10 year old car with an 11 gallon tank and got 340 miles to a fill. I should at least get this with a car that claims to get outstanding miles. I would have bought a Prius. On the other hand this car looks nice. I like the new sporty style and the standards like bluetooth and heated leather seats. I just wish gas prices were not going through the roof. :-)

 

I am getting 9Km/L (you can convert it to MPG). using 2001 1.6L DOHC. in Sri Lanka

 

i have had my 11 gls for 3 days now and im getting 7.6 per 100 kms, i put 600kms on and the guy at the dealer told me it gets better after first oil change.

 

I have a 2001 Elantra GLS 5 Speed manual with 107k miles on it and I get about 22mpg city and about 28 highway. I am happy because I came from driving a 89 Pontiac Firebird Formula and was lucky to get 22 mpg highway.

 

I travel about 27 miles to work, each way. I am using 100% gas, not the 10% ethanol blend. I set the cruise at 60, flat (more or less) interstate, and just kick back and let the old girl take me to my destination. She hit 54.6 mpg last Tuesday (April 6th). The outside temp was 73, and there was a southernly wind at my back. Car had 2,099 miles on the odometer at the time. Today, I only got 51.7...same scenario, pretty much ideal temp as the other day...for what it's worth.

 

Old Elantra, 1999, 2 liter engine, not California bound.

Measuring fuel usage for about 60,000 miles, from 76,000 to 133,000 miles.

Generally was running about 30-31 mpg. Little city driving, mostly country and highway or light city driving.

Gas was 10% ethanol with 87 octane rating.

Tires were filled more than specified, most of the time, from around 36psi to 40psi, cold pressure.

Car got less in winter, 28-30 mpg, more in summer, 30-32 mpg.

Car did best without A/C, windows up all the way or almost all the way.

And car did really good after an oil change, fantastic. And better after spark plugs were changed.

Cruise control set to around 64 mph.

Vehicle is off about 3 to 4 mph with the speedometer. So 64 mph is actually 60 mph. Have timed this with stopwatch and GPS for verification. Looked up in the manual and this is within specifications, unfortunately.

Rarely achieved 34 mpg, very rarely. Would have to be doing in 50's to achieve this. Just enough to get into overdrive or 4th gear. Difficult to keep at this speed since everyone is in a great rush to go nowhere.

Now my buddy with a 2001 Elantra, worse shape than mine, got better mpg, more in the 34 mpg range, he estimated.

 

I'm now up to 2,700 miles on my new Elantra and have tracked every drop of gas. 29.4-32.4 mpg across 8 fill-ups. Typically 31.8. Always 10% ethanol, 50% highway with cruise set at 65.

The trip computer was designed by the marketing department. On a long highway trip, it showed 45 mpg out and 35 mpg back (did I mention hills?) but the average when I filled up was 32.4. Resetting my mpg between tanks yields excessively optimistic values that are not supported at the fill-up.

Mileage aside, I'm still thrilled with the car. Huge improvements since '06. I can live with fuel economy that is good instead of tremendous.

 

Today: the MPG gauge measured 57.7!!!! That's correct! 57.7 mpg. Here's what you need to know, however:

Engine has 2,400 miles.
I changed the oil at 1,900 miles: 5W20 conventional Valveline.
I am running 100% pure gasoline, 87 octane.
I am on a realtively flat surface of Interstate 44.
Distance traveled was 28 miles.
Cruise was set at 60 mph.
The air conditioner was not on, but turned on/off sparingly just to cool.
The fuel tank was 3/4ths full.
AND...the wind was blowing from the south at approximately 30 mph. I was traveling north.
Tire pressure in the 215/45R-17 Continental tires was 37 psi, cold at time pressure was taken.

I did get 54.9 mpg a week ago, with a good south wind.
Mostly, I am getting about 46-49...

 

I got a 2011 hyundai elantra -- i'm getting on average 35 mpg. Drove on the highway and was getting 42 mpg and I have less then 1500 miles on it.

Mine is doing just fine. 42 mpg on the highway.... sitting b/w 31-34 in city. I have done 4 fill ups and my car has about 1300 miles on it. When I fill up I'm maybe putting 10 gallons in.