im don't know much about this sorta stuff so i was wondering wut the button on the shift **** (automatic) that says "overdrive" is for when it is turned on.

 

When O/D is off - the auto tranny will shift into 4th gear
When O/D is on - the auto tranny will not shift into 4th gear

 

better explanation in the faq's. i use it for offramps on the highway to slow down without using the brakes, i also use it when i want to accelerate faster, and when i'm sitting in traffic.

 

O/D is an extra (4th) Gear that you use on the highway, around town you dont really get upto speed to use it. Once your over 50 you use it, if not you'll be running really high RPM's in 3rd gear. I dont even turn mine off, I just leave it. It doesnt make much if any difference since I never get upto speed to shift info 4th except on the highway anyway.. and here in NYC once your on the highway its probably full of traffic anyway

 

www.howstufworks.com

4th gen FAQ

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