This test represents 10 miles of a mixture of rural and interstate highway driving. The engine is warmed up before the test begins and the average test speed of about 48 mph is maintained. The top speed reached is 60 mph. No intermediate stops or idling are included in the test.
The EPA acknowledges that test results might differ from real-world fuel economy ratings. It prescribes the difference to — among other things — the fact that the test cars are in optimal mechanical condition and thus perform better. But by looking at the EPA's testing procedure, it is clear that the habits of today's drivers are not duplicated. On most highways, speeds of well over 60 mph are common resulting in much lower fuel economy ratings. Furthermore, although the EPA tried to duplicate city driving by introducing periods of idling, today's congested roads produce far more prolonged stops. For a more accurate, and up-to-date reflection of the real-world fuel economy delivered by different vehicles, we invite you to look at the results obtained by Edmunds.com's long-term testing program.
At Edmunds.com an important part of our long-term testing program is recording "real-world" fuel consumption. Our long-term test vehicles are driven by a different driver each month. Some drivers have a lead foot while other drivers are mellower. Over Edmunds' year of ownership (and typically 20,000 miles) these differences average out. Furthermore, each month, we record the best and worst mileage we have gotten.
We decided it would be interesting to pull out a sampling of different test cars that we have driven and compare the "real-world" figures to the EPA estimates. Hopefully, this will help you better interpret the numbers you will be seeing on window stickers the next time you go car shopping. We have included different vehicles to get the best possible cross section.