My E4OD likes to slip out of OD when I am on the interstate as I am passing over an overpass or as I am about to crest a hill while traveling 60-65 mph ...BUT only when pulling a 48` car trailer (which isn`t too often, which of course makes my diagnosis difficult), lifting off the accelerator puts me back in OD. I had the FLIP changed and then adjusted by a Ford Mechanic a year ago with the Ford scan tool and the gauge block (I did suggest your voltmeter method, but I got that blank stare, same stare I got at the trans shop that I paid to adjust it WRONG), while this did cure the problem temporarily it has returned.....No codes at the time.....I was thinking of changing all the sensors and relays you all are talking about but for the life of me I can`t find the relays.....in the fuse box (under the hood??) none are marked PCM, trailer or ECM.....help, anyone....thanks in advance!!
...redvetracr@msn.com
PS: truck has 83K miles and has been bulletproof for most of them.