Charles Bird

I have a 96 full size bronco with an with 160000 mi. trouble free,until last week the tranny started to pop out of gear into neutral, and then catch itself. ( with the apropriate rev and bang) I replaced the gear selector switch on the side of the E4od to no avail. The fluid has no burnt smell, and looks clean. When I drive from a standstill the trans shifts smoothly. I changed the fluid at 100000 mi., and have not had to add since.(it doesn't leak.) I've read some motors manuals , but they don't give much info. Is there any electronic code feedback for the tranny like the egr and other motor systems? Is there a chance the gear selector switch is out of adjusment? Is there an adjustment? I'm kind of at a loss so I'm here for HELP...