Four Wheel Drive Only Engages After Reversing
 

Well, here's my tale of woe. Any insight is greatly appreciated.

I bought an 04 FX4 about a month ago, and the first 2000 kilometres have been nothing but daily headaches and disappointments. The truck bangs, and squeaks, and ticks, and grinds, and whistles... it's unbelievable.

But my real issue has been with the four wheel drive system. It worked great for a whole day. I replaced the little vacuum switch thing on the firewall. It worked great for another half day or so. Then I replaced the actuators on both hubs, and it worked great for almost a whole week.

Now when I put it into 4H (electric on dash), even if at a complete stop it does not engage. When I go forward there is a wicked awful high speed grinding noise that's either front and center or front drivers side. The front wheels definitely do not get any power. If I reverse, even just a foot or so, and then go forward the four wheel drive engages fine, although sometimes there is a clunk associated with it.

Any thoughts on what to try next? I love the truck's ride, interior, and styling, but it's gonna give me ulcers.