I was headed back home on a 100 mile trip with the converter locking and unlocking. Or so I think thats what it is. I made it half way and stopped and went to go again and noticed I had no 4th gear. However after I got to town and parked the truck for awhile I got it back. But on the way home it went away again. Any ideas? Im so sick of this. I am about to get a FLT or an 80e.