48re won't shift back into first

[jcarrick]

Hey guys, I just cannot figure this one out! Heres the story:
The truck is a 2006 Dodge cummins and it started not wanting to shift out of first a while ago with no codes. So we replace the governor solenoid and transducer. After this the truck ran great for 400ish miles. After 400 miles it threw codes P1753 and P1756 and sent the tranny into limp mode. We checked to see if the TTVA was moving when the key was on and it wasn't, so we replaced the TTVA and cleared the codes. After installing the new TTVA we can visually see the arm moving now when the key is on and no codes have shown back up, but now a new problem has started. After startup the truck starts in first and shifts great, just like it should, but after the initial go in first it will no longer start in first from a stop unless you manually put it into first. You can also feel it kind of lurch as you come to a stop, kinda like what it feels like when you come to a stop and things settle with the brakes, if that makes sense. After you shut it off and start it back up it will start in first for the first time you put it in drive, and then it wont again until it has been shut down and restarted. Can anyone give me some pointers on what this could be?? I have searched and read for hours but cannot find anything!

Thank you!

-Jon

 

[Bad-Duvall]

Id go back and check/replace the transducer again. about 1 outa 10 are bad right outa the box.

Is this a stock trans?

 

[dangerous06]

I had this exact thing happen! After a month of guessing I replaced the internal harness and all was well!

 

[jcarrick]

Yes, stock. It is definitely getting expensive to figure out with having to pull the pan so many times

 

[dangerous06]

I had this exact thing happen! After a month of guessing I replaced the internal harness and all was well!

Oh I forgot the harness was frying the transducer in mine! So I would replace that at the same time as the harness!
Man I hope you are doing the work a shop would bleed you dry!

 

[jcarrick]

Update: Got in the truck this morning and started driving it and it is shifting totally normal now, even at operating temp...

 

[jcarrick]

Scratch that, after about 15-20 minutes of driving it will only start in second again... And the weird thing is front speakers quit working around the same time it starts to only start in second from a stop ???

 

[dangerous06]

WOW Well clean all your grounds including the tranny to block one!

 

[jcarrick]

All grounds are cleaned, no change. It basically feels like the thing isn't shift back down into first when you come to a stop. You can feel it kind of "lurch" right before the you come to a come complete stop and feel the brake "lurch". Could a speed sensor cause this with no CEL and a properly working speedo?

 

[jcarrick]

Well I got it fixed. Pulled the pan again and checked the wiring harness, it looked good. From there I decided to pull the freshly installed governor pressure sensor and actuator and found that the gov. pressure sensor had two tears on the o-ring. Obviously we can all make mistakes, but I am fairly certain when I put that in the I lubed the o-ring and made sure it seated nicely. It definitely could have been my fault, but I'm wondering if the failure of TTVA could have caused excessive pressure and blew the o-ring out or not? Anyway, it is fixed and driving nicely again. Thanks for the help guys!