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Evening to all. My wife and I are first time owners of a Jeep. We traded an 07 VW Passat towards a new 09 Wrangler X with the 24s package, power package and a bunch of other goodies on it.

My first question is that I noticed the O/D is automatically engaged at all times when you first start up the vehicle, a minor annoyance but I have always been told that for most driving (except flat highway) you want overdrive OFF especially considering that I live in AZ, do a lot of commuting and when we do plan off-road trips it involves going up and down some pretty good sized mountains.

1st:

Is this true? Should overdrive be off for most driving....from what I've been told you can wear out a tranny pretty quickly.

2nd:

Is there a way to disconnect this button or reverse it so it is automatically OFF on startup?

Thanks,
Can't wait to ask more questions and learn from everyone here.

BTW. We took the Jeep up north to Sedona this weekend, popped its cherry by taking it off-road on a trail called broken arrow. Pretty damn cool to be up there....off-roading and having people waive at you...I cant wait until I get rid of these temp tags so I can feel like part of the club...and not some newbie.:bounce:
 

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I always leave mine on unless I am towing something....to be truly honest I never even think about it...when I am offroad, I usually have it in 2 or 1...I have noticed it hunts more since I put on the bigger tires though...
 

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From what I know and have experienced there is no problem with driving in OD all the time. OD is just the last gear and the tranny is designed for it. When towing, I believe most vehicles equipped with OD auto suggest turning it off. Otherwise it is fine.
 

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Congrats on your new jeep !! I am on my first jeep and love it. As far as the od button, I think you will get better mileage and quicker shifts with it off around town and with it on on cruisin trips?? I read that somewhere and it seems to be that way for me? (seat of the pants feel) :bounce:
 

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The only time you need to think about it is on long mountain trips or during towing. The deciding factor is if your transmission is 'hunting' for the right gear. That is, constantly shifting between 3rd and 4th gear. If you find yourself in that situation, just turn off the overdrive until you're back on flatter land.
 

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From what I know and have experienced there is no problem with driving in OD all the time. OD is just the last gear and the tranny is designed for it. When towing, I believe most vehicles equipped with OD auto suggest turning it off. Otherwise it is fine.
X2 Unless it is jumping in/out of OD there is no real reason to turn it off. The transmission is locked up in 3rd and 4th so it isn't slipping and generating heat.
 

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Okay- to explain from a technical standpoint.
Overdrive is not a feature.
Overdrive is 4th gear. "Over" refers to a gear ratio of less than 1.0:1. The button simply does not let the transmission controller engage 4th gear. That's all!
This button should be UNTOUCHED except in towing situations. Also, on a long mountain grade where the transmission may want to "hunt" (switch between 3rd and 4th repeatedly) it may prove useful. If you're off-roading fast enough that the trans could shift into 4th, MAYBE, but then again, slow down! :)
Leave it alone. Using 4th gear reduces engine RPM, promoting better economy, less wear, and lower temperatures. All very good things. Whoever told you it can wear out a transmission is not quite right- on the JK's automatic, that is simply not the case. Ignore all future advice from them unless they learn up on the JK :) Mark W.
 

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Whoever told you it can wear out a transmission is a moron, and does not know a thing about transmissions. Ignore all future advice from them :) Mark W.
Not strictly true, but I agree that they didn't know what they were talking about.

Some transmissions, like GM's 4L60E/65E etc will come out of lock up in OD and slip the TC, this generates a lot of heat and is generally not good for the transmission. However, this does not apply to the 42RLE which will change from 4th to 3rd rather than slipping the TC.

They knew something about what they were saying, but not enough, so yes, ignoring them would be a good idea :)
 

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Sorry- Chrysler training kicked in :)
I worked at GM for a while, and the 4L60/65E's DO do that- they also run beefy trans coolers for that specific reason. That's why a lot of people would come back and see if we could disable that feature- or just get flashed :) Mark W.
 

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I have the auto trans,live in the mountains,only have a 45mph around here so OD I set to off because it does "hunt" on me here.Ain't no thing and really doesn't effect mpg much at all,if any.
 
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