i have a 2001 f250 7.3 automatic that I've been working on trying to get the bugs worked out of the transmission for a little while now, it started when reverse went out, the truck would stall the motor in reverse sometimes and sometimes not. I took it to a transmission shop since the guy that normal works on my truck was busy and has a pretty good wait list to get in. the trans shop tore into it and found metal in the pan, informed me I needed a new trans, so they put one in and when I got it back it still wanted to stall in reverse sometimes and sometimes not, I took it back and they looked through it again and found nothing. so I consulted with the normal mechanic and he asked if they changed the tss and oss which they hadn't, and he said maybe one is a little off and is causing the pcm to stall the motor trying to get the output and input shafts in harmony. So I decided to replace the 2 sensors and try and rid this transmission of its problems, when I went to get the new sensors the part store only had the oss and I had to order the tss. while I waited for the tss I put the oss in and replaced the pigtail with it since it had been broken in the past. after getting it back together the stalling in reverse seemed to have gone away but when driving down the road the trans started shifting hard and through codes p0717, and p0715. which is weird because I never had them before and I put the old sensor back in, but I figured the sensor must have gone bad while I took it out and it traveled around town look for a new one, so I waited for the new one and put it in only to have the same results, 1-2 was smooth, 2-3 was hard under acceleration or would bogg the motor down like it shifted way to early, and 3-4 was a hard shift but not as hard as before. After consulting my mechanic again he instructed me to test the sensors, ohm the wires to the pcm and check for voltage from the pcm. I found the sensors seemed to be in working order, all four wires between the two sensors ohmed out to 0.4 which should be in range. But I could not detect much voltage from the pcm, I was only able to read about 50mv from the pcm, my mechanic said I should be getting around 5v from the pcm. This is where I am stuck nownot sure what or how to proceed from this point, does anybody have any suggestions that may be able to help me figure this out?