05 Hyundai Tuscon poor gas mileage


I recently purchased an 05 Hyundai Tuscon with a 6 cylinder engine. It had 16,000 miles and I’ve put on another 1000. Love the car but it is getting only 19.5 mpg at 70 mph and about 15 in town as opposed to the 26/22 the literature says it will get. The dealer has tried to diagnose the problem but everything come out normal. Any idea what the problem is?


This may be the best it can do. Wind resistance increases with the square of the velocity. The 26 miles per gallon rating may have been obtained at a lower speed than 70 mph. I have no idea how the city mileage is obtained. Two things that are easy to check: 1) tire pressure and 2) odometer accuracy. Tire pressure gauges cost less that $10. Check your odometer over a 10 mile stretch of interstate highway.

Finally, fill your tank. Keep track of the number of gallons of gas you put in the tank over the next 1000 miles and refill the tank. This should give you a fairly accurate estimate of your overall mileage.


You might read through this and forget the overly optimistic estimates in the literature you read.


The mileage numbers quoted in “the literature” and on the window stickers of new cars is measured under carefully controlled conditions. The vehicle is on a dynamometer, inside a building. The numbers DO NOT reflect real-world driving conditions.

This will change in the future, but for now the mileage numbers you read should be considered “best case scenario,” or perhaps “in your dreams.”

19.5 @70 mph doesn’t sound out of line to me, considering the vehicle type and engine size.


Consumer Reports got 18 MPG overall. Yours is right in the ballpark. Their gas mileage seems to agree with what people are reporting here when they are surprised that the sticker on the window is not accurate.


This is fine. Well, maybe not fine, because that’s a relative term. But it is the norm. Those “expected” numbers were plotted for much lower speed, probably 55 mph.

How are you evaluating your mileage numbers?



Few if anyone makes the sticker mileage, although next year a fair number may as the lower numbers will be closer to the real average.

Second it would appear to me that you have something of a lead foot. Ease up take life and driving a little slower. In most places 70 mph will not only reduce your mileage, but it is as illegal as sneaking across an international boarder. Easy driving in the city will help a lot there also.


70 mph? And the OP is questioning his highway mileage? Yes, I also drive at that speed occasionally, but I do so knowing that I will pay a mileage penalty for that speed.

The published highway mileage figure that the OP quoted was achieved by operating the vehicle on a laboratory dynamometer at a steady speed of 55 mph, while not operating the a/c. And, of course, when operating the vehicle in a climate-controlled room with a dynamometer, there is no wind resistance to overcome. That, among other reasons, is why so few people achieve the published figures for gas mileage.

As was already stated, the EPA is changing the way in which gas mileage is computed, and as a result, the “new” figures should be closer to reality. However, I can guarantee that they will still be based on legal speed limits, and in most states, 70 mph is not legal.

And, as to the city gas mileage figures, if a vehicle is properly maintained, it all comes down to two factors–the specific driving habits of the driver and the specific traffic patterns in which he is driving. Neither are likely to precisely match what the EPA or the car manufacturer experienced.


Actually on the Interstate in Ks. 70 is the speed limit.
I would be more happy with the mileage I’m getting if I didn’t have friends with the same vehicle that are actually getting 26 to 28 mpg at 70 mph. Also, the RPMs are a bit high and I have an appointment to check that.


Matt, I am evaluating mileage by filling the tank and then, when I fill it again, dividing by the gal.s on gas put in. I have this about 10 times so I believe it’s accurate. Also, the odometer is accurate. I got much better mileage on my 03 Jeep Grand Cherokee (bigger and heavier) and most of my friends with the Tuscons are getting close to the 27 mgp.