Sorry if this is in many other threads... just was reading this article on BusinessWeek, and saw these comments:
http://www.businessweek.com/bwdaily/...n_id=rss_daily
# Gau Mar 11, 2008 3:16 PM GMT Actually no, 55 isn't the most efficient speed The best ratio for gas is just above minimum rpm in your highest gear. RPMs is what eats gas, not speed... t Generally older cars run from 45-60 depending on gears and ratio. However on a lot of newer higher end cars with 5 and 6 speed gears, those number goes up...
# Tobin Mar 11, 2008 3:09 PM GMT the difference between gas savings at 70 and 55 is negligible on today's vehicles, in fact some cars in overdrive have better MPG at 70 than at 40 or 55
Is this true?