I have manual locking hubs. 4wheel hi and low. 4wd works excellent but it's happened a few times recently where I put it into 4wheel and give it gas and nothing happens-no rear wheel drive, no 4wheel drive, just engine reving. It doesn't even make a sound, just no forward movement. I take it out of first, back into first, still nothing. Then I put it into 2wd and back in 4wd and maybe it works, maybe not. Eventually it goes into 4wd. Then out again into neutral-while still in first gear. Finally I tried going into 4wd low and it didn't pop out. Then from Low to High and it held. It never pops out of gear in 2wd. Maybe shift cables are off? I figure if it were the hubs that 2wheel would still work. Anyone dealt with this?