Lifter tick

[Theichelberger]

So my 2000 4.0 ranger used to have multiple lifter ticks, but now after replacing all of the pushrods and rocker arms I'm just left with one lifter ticking from the sound of it, but what I find odd is that what you start the engine when it's cold it's completely quiet, once it warms up it begins to start ticking. My question is what would cause it to start ticking once it's warmed up?

 

[Uncle Gump]

As tke vehicle warms up so does the oil. This naturally causes oi pressure to drop.

 

[Theichelberger]

In that case would this be a sign that the lifter is beginning to collapse