A terrible weird noise...help

[Aarons72]

I know this is nearly impossible to figure out over a forum but I'm hoping someone has experienced something like I can describe.

For about two weeks every day I drive my truck I hear this nasty rattle/clicking/possible grinding sound...it only happens when I'm driving and it only happens when I'm accelerating... (not power braking, not coasting, not in park) It's the worst when I'm going about 30 or when I'm going steady up a hill. It's not really loud but my wife hears it, my uncle hears it and one of my friends that I took for a ride could hear it. I have spent about 12 hours under my truck and under my hood tinkering with stuff trying to eliminate the noise and it is driving me crazy. In the mean time I did fix some other problems I didn't know about though

Any tips would be very appreciated