Hey guys, I own a 2000 ES300 that likes to be real picky about overdrive. I've noticed that when I fire up the car and hop directly on the interstate it will go into overdrive, but once the car is warmed up it wont shift anymore. I'm a college student and I travel alot, it bugs me that my car runs at around 3500 rpm cruising down the highway apposed to 2500 like it should. I've taken it to a transmission shop and they couldn't do anything, afterwards I took it to my dads mechanic and he messed with it for a month, no real improvements. It's a pain because this is a really nice car that drives extremely smooth. Anyone have any suggestions on what they think it may be?

 

do you know the difference between overdrive with torque converter in lockup and decoupled? how many gears does this transmission have? what gear is it in? when you're going one way on your trip is it higher RPM than the reverse direction on the trip?