2009 Silverado HD 3500 DRW stock
New old guy, started a thread trying to get some help with this 0741. After reading as many forums as possible with the multiple checks performed went with TCM R&R was told that A40 replaced by T14A. I received T14 supposably coded with Allison doc to my vin. Same symptoms no matter which TCM is plugged in. Hard to condemn TCC with such intermittent issues and only seems to throw code when pulling load which in old school means slipping torque converter but after researching Allison with all its sensors and module readings to perform correct shifts at correct times was curious, all I have to scan with is auto ingenuity cannot command torque converter solenoid. Went with one diagnosis of oil in pass through plug at rear of transmission, cleaned dried but noticed while drying weeping fluid next to pins on transmission side of plug I understand there is a seal to replace there, understandably oil or moisture inside of plugs can cause crazy conductivity so praying.What has me concerned is issue only prevalent when hooked to trailer empty 6700 lb only at six gear shift with noted transmission temperature gain. I have already serviced and fluid that was removed was clean magnet minimal sludge oil out of filter no noticeable silt. One of my questions is on my scanner my engine speed sensor has given me 0 or mirrors RPM, turbine speed mirrors RPM zero slip counts ISS mirrors RPMs OSS approximately 1100 difference while driving connected to AE. I've read as many TSB and TCM forums that I could find. Allison shop in town Said he needed me hooked to trailer to scan if they do not have a scan tool that can simulate load or stall or whatever they need ,that made me hesitate, but I'm at that point has anyone experienced these same symptoms, I was hoping speed sensor or throttle position sensor difference when under load could be issue because the Allison torque converter I understood to be strong and reliable. Any help would be appreciated thanks. Thanks for letting me in the neighborhood.