5.7 oil pressure issue

I've seen alot of threads on 1st gen issues but heres mine anytime I'm cruising or idle under 2k rpm the oil pressure gauge slowly drops and on start up it takes awhile to move it just started doing this had oil changed in fear of filter collapse and I'm currently driving from Pensacola to tampa cruising 85 holds steady just shy of the mark in middle what the heck pump getting weak?

 

The gauge isn’t ultra sensitive(i take it as it has normal pressure or it dont).

On cold start, mine creeps on the 3/4 mark. At operating temp its around 1/2 way mark(maybe a hair under at idle or a little over under throttle).

153k miles. Always been this way. I run 0w-30 Amsoil, but have ran 20w and saw no obvious difference on the gauge.

 

Yea that's where mine used to ride now its moving kinda sketchy just hit 150000

 

Sounds like the oil pump is fine. IF your filter has collapsed, then good oil pressure at 85 mph may not be too surprising...the oil flow would be completely bypassing a collapsed filter at high engine speed and oil pump volume. (Dirty oil is better than no oil.) The bad news...it would be unfiltered oil.