I posted a while back about a weird surge / slip issue I was having in 3rd gear (auto) at highway speeds. Replaced my TPS twice now with Borg-Warner parts thinking maybe the new one I had went bad quickly, but this is still occurring with some regularity. I have had the truck back into the shop that did the tranny work and they say their tests all come back ok as far as the transmission itself is concerned and believe this to be an outdated PCM software problem. The gave me this TSB, which they believe is my problem. I'm not sure if I buy that since this is a "new" problem that hasn't always been there.

The problem is that while in 3rd gear (whether it be by downshifting up a hill or having O/D turned off) as 65-70mph is achieved with a constant throttle the truck with hop around about 2-300 RPM back and forth. If I floor it at that point it will jump about 500 RPM and pull from there, if I back off slightly it will drop a few hundred and pull from that RPM. It almost feels like it is trying to shift to some magical gear in between 2nd and 3rd. Occasionally, following this weird surging, if using O/D, it will stick in 3rd for about 3-5 seconds before downshifting back into O/D, almost like it sticks in that gear.

This may be related or unrelated. When in normal acceleration the 2-3 shift feels like it occurs in 2 parts. It will shift down about 200-300 RPM and then fully complete the shift about a second later. It has always done this since I had the old transmission and continues to with the rebuilt one that is in it now. That 2 part shift is almost what it feels like the transmission is doing @ 65-70. It feels like it kicks back to that in-between spot in the normal 2-3 shift.

If anyone has any ideas I'm open to input. I really don't want to take it to Dodge to have the PCM reflashed with the new software only to have this be something else and me be out a good chunk of change.

 

there was an issue with the tranny that I cannot recall, I did ask for a pm on it and dont remember what it said. most likely I still have it, let me go look. they symptoms were identical to the tps problem...

 

I had this trans computer re-flash done on my 2001 to helpfor a surge at 40-45 mph. That surge is actually the trans TQ locking and unlocking. As the bulletin says : this flash removes any TC lock-up in 3rd.gear and raises the lock=up to above 50 mph. It made a tremendous amount of difference in mine. However, your description of your problem makes me wonder if this would have any benefit for the concern you have. I was not having any shift problems with mine and it sounds like you may have. This may not be of any help - but just my FYI. OH - I just thought : you might want to replace your TPS and see what effect it has : cheap and easy to do and would be worth trying.

 

here it is... have a look. https://dodgeforum.com/m_538721/tm.htm

 

That's VERY interesting about that wire. I looked on the wiring diagram and it is an orange wire. I will DEFINATELY check that the next time I have my trans pan off. Thanks for some GREAT info.

 

Thanks for the help guys, I'll have to check that wire out the next time I change my fluid. I tried something tonight as well after reading everything I could find on here. I reset my PCM by removing and grounding the positive bat cable for 60 sec. I took the truck out for about a 20 min ride to see if there was any difference. Besides not showing any signs of the problem I was having, it also has a bunch more pep off the line. Before I could hardly squeak the tires (even with the CPS mod). After the reset the thing breaks loose almost too easily.

I'm going to drive this around for a few days before calling the problem gone, but it seriously went away for the time being by reseting the PCM (which I neglected to do after putting a new TPS in).

 

started thinking about this more and if the wire is an issue, you'd see it as soon as it goes into OD and the TC locks... could be a speed sensor since it only happens at a certain speed... there is one in the tranny & one in the rear diff... check the tranny one 1st.

 

Well, after a few miles more driving it came back.

I replaced the speed sensor on the tranny. That thing was covered with black metalic shavings... It makes me wonder if they just threw the same sensor back onto the new tranny without even cleaning it.. the fluid isn't dirty now. Didn't fix the problem.

I'm going to change the fluid today and inspect the filter and see if it's clean or trashed or what. I'm getting a little annoyed.. but such is life I guess.

 

if you recently had major trans work done at a shop and then find metal shavings on the speed sensor : I think I know where I would be heading very fast : the trans shop

 

Been there already. They inspected and tested and said everything mechanically was fine... ... ... Its going to a different shop (it was a chain place that did the work, so I'm taking it to a different location).