"Fuel Economy Guide data is derived from vehicle testing done at the EPA's National Vehicle and Fuel Emissions Laboratory in Ann Arbor, Michigan, and by vehicle manufacturers who submit their own test data to EPA."

Quite trustworthy to submit your own data, right?

Further searching reveals ...

"The city test is approximately 11 miles long and is a stop and go trip with an average speed of about 20 miles per hour (mph). The trip lasts 31 minutes and has 23 stops. About 18 percent of the time is spent idling (as in waiting for traffic lights). A short freeway driving segment is included in the test. The engine is initially started after being parked overnight."

"The highway is a 10 mile trip with an average speed of 48 mph. The vehicle is started "hot" and there is very little idling and no stops."

While I can't say too much fault with the city driving (beyond the fact that it's still tested in a lab versus reality), the highway speed is simply laughable.

Cars designed for the US will be optimized for these specs only, whereas "world" cars have other fuel economy tests to abide to - typically one that better suits the typical real-world driving speeds.

-- Kane

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Blossom II - '91 745Ti/M46 ... Bubbles - '74 144GL/BW35 ... Buttercup - '86 245GL/AW70 ... The Wayback Machine - '64 P220/M40