Thanks for your interest. Bex also told me to unplug tcm and I will,promise. I have the 4 speed od transmission. We are in bad weather now,I will post results in a day or two. So far,what I know, driving in drive,engine tach revs up,its like transmission goes to neutral. When I let off throttle,vehicle reengages back in drive. So far this is sporadic. I will go to AutoZone and scan for codes tomorrow. Thanks Oren
I don't know how much help this will be but I doubt it's electrical - you have one of two possible automatic transmissions, I think the first is known as the 3L30, but, the important part is it's a 3 speed transmission with very little in terms of electronics, so nothing electrical to engage/disengage and prevent it from moving, the second one, which is more likely to be the one you have is the 03-72LE, a four speed (actually 3 + OD) which is electronically shifted, but, the electronics only select which gear you're in 1, 2, 3 or OD, and you can actually unplug the transmission control module and drive using the shift selector (it's cable operated).
Neither transmission has any electrical selection that would prevent the vehicle from moving.
Transmission is going in and out of drive.I have changed oil and filter. This happens sporadically. Motor continues to run, tach climbs. Let off throttle,goes to idle,then reingauges. Seems electrical. Thanks Oren.