here in the foothills of southwestern PA I usually tool around in Drive to prevent unnecessary downshifts from OD to Drive because of the inclines. my 3800 just can't hack it. I'm thinking this practice extends the life of my transmission. the only time I use OD is on the highway when I know I'll be able to maintain a steady speed of at least 55MPH. is my theory a sound one? what are your driving habits? do you just shift to OD and let 'er rip? or do you do what I do when your in heavy traffic/ going up inclines, ect.?

 

My wife always insists that I drive her old Bronco with the OD off, as she swears this extends transmission life. I think its a good theory, but hard to prove. I never worry about it with the Monte or the Regal, which I probably should as they both have the same notoriously crappy transmissions.

I pledge to try driving with the overdrive off more in the future :p

 

I always stick it in OD....I think 50-55 is a bit fast to stay in D all the time...My Monte goes into fourthgear (OD) at 40 mph. Also, you'll get better MPG's in OD...
the only place i think it is a good idea to stick it in D in when you are climbing through hills or mountains for extended periods of time...

Good theory though...but I don't think it really matters much...My 89 silverado has spent its whole life in OD and its at 230K orig. tranny..

 

i just leave it in " N " for NOS!!! lol or " R " for RACE!!!! haha.

really, i just leave it in OD, unless im pulling REALLY steep hill / im in my development, then i shift down into drive before i hit the hill.