Overdrive, What is it and whats it for? Options

[LewFX]

Does anyone use their overdrive button?? Is there any advantages? I hear its suppose to act like a 5th gear..any comments?

[celicasupra209]

my impression is that overdrive is automatic version of downshifting since its an automatic it shifts gears automattically but if your in a manual and you down shift you get the same results as using and overdrive button maybe im wrong but thats what happens when my uncle uses his od button on his 240 auto its accelerate faster and rpm jumps same thing like down shifting you accelerate faster .. just do use od when going like 60+ mph i dont think its a good idea especiall if its on a celica lolz