Bought a JD 5425 with power reverser, 05 model, cab, with 960 hours. Drove it around the place for 20 minutes checking everything out before I brought it home. Got it home and drove it around for a while checking cows and such. Started down a hill and the tractor kicked into neutral and beeped three times and flashed the red light on the dash. It continued to do this 4-5 times in a row within very short distances. A friend of mine is a tractor mechanic 2 miles down the road so in drove it over to him, it did it 3 times on the way. He checked the switches, and solenoids and drove it around for an hour and it didn't do it again. I picked it up and drove it home and it didn't do it for a week. Yesterday it started doing it again. The lever is in the forward position, if I pull it back to neutral and push forward again it takes right off, may do that 1-6 times in a row then be fine. It seems to be worse in wet weather, and when going down hill. Any ideas?