changed water pump and thermostat but still loosing little water in radiator. changed oil sending oil pressure is back where it should be but has a tick you can hear it better from the bottom end held a board against block doesn't sound like something is knocking just unsure of problems

 

Let me guess . 300/6 and you are hearing the ticking near the bottom of the bolted on inspection plate on drivers side?

If yes i would tend to think a stuck lifter. Thats their home location. Pull valve cover, loosen rockers . Remove push rods. Then pull off the plate and change the lifters.

 

the tick is pretty much in the middle when you are underneath the truck

 

Exhaust leak? They can sound like a tick. That location doesnt lend its self to having a metal object ticking. Hard to say.