Ok, so here it goes...Last year my family and I were driving to Kentucky and in Mid Ohio I noticed the battery light come on. I kept an eye on the volt meter and when it reached 10 volts I decided to get off the freeway and fix it. Well when I got off the freeway and was stopped the light went out and truck started charging again and was at 14v. I went to closest parts store and just bought a new alternator instead of screwin around. I installed it in the parking lot and we continued on. Well about 5 min later the light came back on again and same story except this time I bought a new battery, thinking it was bad cause it was 4 yrs old at this point....Nope, same thing. So we finally make it to Kentucky, 3 batteries and 3 alternators later. It was intermittent for awhile during our trip. Sometimes it would charge and be fine all day, other times it wouldnt charge at all so I would take all three batteries and charge them overnight in our cabin and take them with us and change em out when one would die...Well, on our way back from Kentucky I noticed that the truck would charge perfectly fine if it was in reverse...I dont get it either..But it would...So off we went, I would drive until it got to below 10V then pull over, put it in reverse and sit there for 20 min and let it charge. Then as soon as it goes in drive it would quit charging...For a yr been dickin with this so I finally cut the field wire that goes from the computer to the alternator and I spliced it into the fuse box at a switched fuse so atleast when the truck starts it charges with no problems. But whatever tells the computer to send voltage down the field wire is bad because the light still comes on and off but because I bypassed the computer the alternator works regardless....Anyone have a clue as to why this is doing this?