New owner: Overdrive?

[DebWNJ]

Just picked up my 04 today, and (having a senior moment), I cannot recall whether the salesman told me Overdrive is better on or off. I've driven stick-shift cars for the last 30 years, so I don't even know for sure what Overdrive does (and doesn't do). I do a combo of highway and non-highway driving on a daily basis. Can I switch it on or off while the car is moving?
Many thanks for anyone who can offer some tips!
Deb

[Greenzter]

Overdrive is like another high gear. Good for fuel economy. The button will prevent the tranny from going into overdrive. Unless you're pulling a trailer or drive in mountain regions, leave it alone.

Modern automatic transmissions are smart. Always use 'D' and forget about it. :)

[kingstevecrv]

a over drive button is for highway drive,saves on fuel.for towing and that extra boost of power when needed for passing when you take it off

[Travelor]

By pushing the button, you disengage the final gear in the automatic transmission - not engage it.

This helps by causing the transmission to not hunt back and forthe between the final gear and the next one.

[GTCB-chris]

it keeps the car from shiftng into final gear, not to boost power, but to keep the engine in a lower gear for more tourqe

[fillsteak]

I have an 01 V automatic and I use it to fake a manual transmission.

So my V has 4 gears. Overdrive controls whether or not to use the 4th gear. In tough times and snow, I manually select 1st (1), 2nd (2), 3rd (Drive, Overdrive Off, 4th not allowed to be engauged), or 4th (Drive, Overdrive On, 4th allowed to be engauged). This usually works if I play my RPMs correctly.

It is also useful on highways to turn in Off and sink back from 4th gear down to 3rd without physically braking (now engine braking and all that jazz). This, unfortunately, I use more often than I'd like on tailgaters riding up my V's arse as I engine break and start to slow without brake lights going off.

As a note, I might have the terms Overdrive Off and On mixed, but you get the idea. For my 1st gen, if the OD light is on, then I'm limited to 3 gears, otherwise if the OD light is off, then I have full range of gears.

Try it out on a steep hill!