General Overdrive ?

[LastExpo2000]

I've never had to use it before. When would it be best to use overdrive?

 

[panda24619]

you shouldnt have it off. all it does is allow the transmission to shift into 4th gear. why ever turn it off? when your towing a big/heavy load. 4th gear isnt good when your towing a lot of weight. other than that you shouldnt have to ever turn it off. unless your about to hit a very steep hill on the highway and want to get a running start. but if you floor it it should shift into 3rd or 2nd depending on how fast your going anyways. should you shouldnt have to turn it off.

 

[jacks3am]

overdrive on you have 1st 2nd 3rd 4th and overdrive, o/d off, you only get 1-2-3 so yea turn it on lol

 

[LastExpo2000]

So have it on at all times? Does it provide better gas mileage? Also where I live its flat, but I'm leaving for a trip this friday and the highway is going to get very hilly.

 

[panda24619]

So have it on at all times? Does it provide better gas mileage? Also where I live its flat, but I'm leaving for a trip this friday and the highway is going to get very hilly.

just leave it on. the tranny will shift into 3rd if it needs it. you shouldnt be shifting an automatic tranny. at least down. up isnt too bad, but down will hurt it.

 

[dougmcp]

I even tow my boat with overdrive.
In the hills, if you feel the transmission hunting (dropping down then going back up repeatedly) then you may want to take the OD off.
It is on by default every time you start your Expy.

 

[alaskanexpy]

i lock mine out whenever i get in the truck(all my trucks). i HATE a tranny hunting for gears. i live in a hilly area plus i drive aggressive. so around town i keep it locked out. only time i allow it to shift into 4th gear is on the highway 65-up mph. also keep in mind the more shifting it does the more heat it creates and heat is the main killer of auto trannys.