Ticking Noise, Ford explorer 2000 AWD 5.0 A ticking noise coming from the front part of engine

I have a 2000 ford explorer AWD 5.0. It started to do this noise from one day to another, this noise is coming from the front part of the engine. I replaced the timing chain, It didn't go away, I dont know what it is, i already spent Alot $$, Can any body tell me what it is. The sound is not loud, And it sound the same when park or in the road. ( it sounds like the fun is hitting something) but it is not. PLEASE HELP ME!!!!!