Transmission problem
1995 Ford F150 V8 Four Wheel Drive Automatic rebuil miles

My '95 Ford F150 slips out of gear, generally in the higher gears. It started with hard shifting and has progressed over time. It may go many miles before it does this, or may start right out of the driveway. When the gear "slips" it will often re-engage with a jerk. Does this sound like a rebuild or a less serious repair. Would like to have an idea before I put it in the shop, because like most I have no knowledge of transmissions. Thanks