Well I accidentally came across a way to lock out OD today. I was shifting from 2 to D and noticed that before I got to D the truck shifted into third and locked. I decided to see how it would drive in this position and whatta ya know it won't go into overdrive. I tested it for about 15 miles and it works great. Couple of things to note: I don't think it would be best to stay in this position if you are going from a stop, the transmission basically skips 2nd and locks right into third. Also the TC will stay locked while your foot is on the go pedal or on the brakes, but will stay unlocked in 3rd while when not doing either of those. This obviously still isn't a perfect fix, but works better than anything I have tried so far. Again the only way I can make this happen is to shift into 2nd, then move the lever up like you are going to shift back into D. There will be a notch right before D, the indicator will say you are still in 2nd, but it's not. Give it a try and let me know what you guys think. Thanks



J

 

I have heard that you can downshift into second at higher speeds and it will just force the tranny into 3rd. It will eventually downshift to 2nd if you slow down or just stay in 3rd as long as your RPMs allow it. I have not tried this yet so I can't say for sure. I haven't noticed an "in between" gear in my truck but I will be willing to look for it the next time I am in mine. I am wondering if you got it in drive just long enough for it to hit third but really it popped back into second gear....but since it was already high enough RPMs it just stayed in third. I am curious to know if anyone else has discovered this mystery gear?

 

I want to clarify, this IS NOT the same as the 2nd gear lockout trick. This will allow it to shift into 3rd and stay locked in third regardless of speed or RPM's. In fact you can come to a complete stop/restart and it will shift into 3rd and stay there, although like I said in my first post it makes a very quick shift from 2nd to 3rd, really never even stays in 2nd unless you are on the throttle pretty hard. While in this notch if you shift up into D will go into OD, it you click down into the "actual" 2nd it will downshift into 2nd. This is a grey area and it works, although not perfectly. You can almost tell that the tranny is a little confused. However for towing at 30-55 mph it through hills it will work great, which is exactly where I want it to lockout OD. I'll continue to test it this weekend and let everyone know how it works.

 

Well I got mine into this mystery gear. It is VERY sensitive on placement but it does seem to work. It is literally between the two gear selections so if you barely touch the lever it will pop into either gear. Cool find though.

 

my 04.5 does some funky things if I don't get it back in drive after coming down some hills, I knock od button then d shift from drive one gear and tap the pedle, she's locked in 2nd for the hill, get to the bottom and tap od button and put it back in drive and make my turn, many times I will not get it all the way in drive and the "D" does not light up and man does the tranny act funny, can't describe it but I know whats wrong when it does happen. almost like it goes to brain dead mode with no electronics just presure shifting.

 

Well, I can get it to do it but if I get on the throttle hard enough it will downshift to 2nd and stay there. In addition there is no "notch" that the shifter will stay in on mine. I think what's happened is the VB has enough movement in the shift piston to go to drive but not enough to uncover the port for OD. There is also a micro switch in there that is supposed to provide feedback to the ECU that may not be in the correct position for OD. That in itself is not bad but the jump shift from 1st to D indicates there is some bleed over in the shift ports which may or not be good.

Interesting find.

 

This is a bad bad idea. there is no detent notch between manual 2nd and drive. you are esentially causing a between gear and you may be partially engaging the 2nd gear band and the direct clutches at the same time wich is very bad. you may not feel it happening but if it.... is the clutches and band will fry!!!! It is usually stressed in most manuals that it is very important not to be between detents on cable adjustments....if you keep doing this keep us posted on your progress.........

 

Isn't that what the tow/haul button is for?

 

Not on the 05's...we don't have OD lock-out. That button just changes the shift points. Thanks HorseHauler for the info....edited.

 

Actually it's just the 05's. DC got smart again and added the o/d lockout on the 06's...

 

That would make total sense as to why it acts so funny. I will hede your advice and discontinue this practice. I must admit I am disappointed though, I thought I may have found a way to make this tranny work like it should!!! Oh well. Thanks

J