...That's what I thought too, leaving OD off in the city, but as soon as you get over about 40 mph or so, you can get the torque converter to lock up. So depending if you have steep grades or lots of traffic lights, this might not be a bad thing.

On flats with the torque converter locked up, you will get a lot better economy than with it off, even at 40 mph, provided the terrain allows it.

 

I know there has been talk about this before, and some were seeking a way to have it default to the off position, I don't know if there was ever a mod that was devised to do it. You might want to try and search it out and see (try the electrical and write-up sections).

 

Thanks for the replies guys
I just find it strange that the default is overdrive on........... not what you want when moving off. I only put the overdrive on when I'm travelling on the freeway or able to keep a steady pace over a decent distance. With the overdrive on I was getting 14 L/ 100km around town, with the overdrive off I get 12 L/100km

 

It's like that in pretty well every modern vehicle that I've ever driven. Except my '88 4Runner, may it rest in pieces, there was a button on the side of the shifter itself that would stay in the O/D off position until you pushed it again. It was a very handy location especially being a 4 banger.

I think the main issue though is that it is easy for to forget and then drive 300 miles, and some people don't even know what the O/D button does I'm sure.

 

It may be a nuisance at first, but I know for me it has become habit to shut it off because I have to get on the highway just down the road from my house. For me it is no different then the other things I habitually have to do to get the Jeep going (push brake, remove emergency brake, put in gear, etc).

 

Yeah, too bad it's not in a better spot, though. My '02 KJ is in the perfect spot. I back out, slip it back in D and hit the O/D off button in one smooth motion. Like habit now.

I, too, have seen a slight (bit obvious) increase in mileage with the O/D off most of the time. Remember, I'm on Guam, too, so I rarely see speeds above 45-50mph for more than a few minutes time.

I'd LOVE to find a way to lock mine off as a default.

 

Every car, truck, suv etc that has an auto trans with electronic overdrive button has overdrive on as default. This is because 99% of the people on the road aren't lifted or towing anything.

Can you picture the average housewife remembering to push the overdrive button to turn it on everytime she were on the highway in her honda accord in order to get that highway gear?

Pushing the button turns the OD off because men will remember to do it if necessary where women will not.

 

So is the OD in the auto JK a real gear or an electronic clutch type? I just pulled my 2700lbs travel trailer for over 400 miles and on occasion I would forget to hit the OD button after getting gas or stopping to eat. It pulled fine until we hit hills (5+% grades) and I would notice it shifting down into third.
If it's a real gear I don't see why I can't pull with it, I would rather run in a lower RPM. I'm running 4.88 and stock tires and when I did have OD on it never felt like it was struggling with it and downshifted just like it always does going up hills.

 

Did you reprogram the computer for the new gear ratio?

One reason for towing with O/D off is to keep the torque converter locked, reducing heat.

 

Yeah, with a Hypertech programmer.

reducing heat... that's why Jeep has issued a recall on the auto's they have heat issues without towing anything.
I've added trans cooler just for towing. I need to get one of those scangauge to monitor the trans temp.

Honestly I didn't notice the transmission behaving any different from what it normally does. Before I changed the gears it was always downshifting on hills anyway. The converter may have taken a hair longer to fully engage, but thing dramatic.