Hi All
My first time posing a question.
I have a 1995 Nf 6 cyl Fairlane and when your cruising along in top gear the gear selector on the dash display suddenly disapears for up to 30 secs or so and the gearbox kicks back to third gear. Then the gear selector comes back up and the car goes back into top gear. Anybody have any ideas or if its happened to them, what was the problem.
Thanks.

it will be a faulty gear position switch on the side of the gearbox

Agree with TROY. +1, Change the inhibitor switch.