I don't profess to know a lot, but I DO know that one must NEVER NEVER try to climb a hill in OVERDRIVE. In essence,, overdrive is the HIGHEST gear that you have on your transmission. Therefore,, to climb a hill, any of you girls that remember driving a standard,, KNOW that you DOWNSHIFT to get more power to climb, and then Upshift when you get on level ground,, to the highest gear. Sound familiar?
Overdrive was designed to achieve better gas mileage. Just a little ditty I learned from my ex.. the mechanic.
Good luck to you all!
and HAPPY NEW YEAR!
the best of travels in 2010!!!