Trans question shifting hard into 3rd

[mvalentine6]

New to the site and new to diesels. So i geuss you can say i am a noob. I have a 95 F350 CC Dually and here is my issue. It will shift into 3rd and then hit hard and hit hard going into 4th. Sometimes it does it and sometimes it dont. Depending how i am driving. I did just put a chip in and if i am using the chip it slams into those 2 gears so i dont use it other then in the stock mode were it wont do it as bad. Had it scaned and all that was on there was a po117 and a po603 which should have nothing to do with the trans. Everything looks and seems good with the fluid so i am perplexed. Any help would be greatly appreciated. Also told to it could be the PCM but not to sure on that one.

[CT Performance, Inc.]

Take the chip off...works fine then its the tunes...who's chip?

[mvalentine6]

Thats what i was thinking at first so i took the chip out and and still the same. But it was doing it before the chip. I did notice that before the chip it was running rough and when i took out the chip it went back to running rough. I put the chip back in and it cleared up and started running just fine but still the trans issue. Maybe the pcm is going bad but i thought with most electronics there good or bad.

[esuitt]

Subscribing just in case you find an answer. Mine does the same thing.

[mvalentine6]

I am hoping i am not over thinking this but i notice its not unlocking the converter. So maybe the pcm is going bad. Can the pcm slowly go bad? I don't know maybe i am over thinking it.

[mvalentine6]

Well here is to having no life and a sickness for finding information. I have found what mine is doing and its sayng it is the transmission lever position sensor (MLR/TR sensor). So i am gonna try that in the next couple days and get back to ya about it.

[leojr]

Originally Posted by mvalentine6

I have found what mine is doing and its sayng it is the transmission lever position sensor (MLR/TR sensor).

How'd you get to this conclusion? I believe I have the same issue but get no codes with my 'top of the line Pep Boys special' code reader.

I have noticed that pulling my gear selector our of park is more of a "pop" than a normal feeling movement.