i just got a 2000 2500 and wouldn't you know it a week later the 4 wheel drive stops working, i put a new push switch in it and still no luck, the fuse is good in it the kid who had it before me told me he just put an actuator in it so i don't believe it is that either, when i hit the 4 wheel drive high button i can here the actuator try to engage but a few seconds later it stops making noise and goes back into 2 wheel drive. does anyone have any thoughts on what it could be and what i should do next?