Oil pressure zeros when braking

Hey guys im new to the site reason I'm posting
I just bought a ford excursion 03 limited from the original owner. I never checked the oil level when I first bought it

I'm having my oil pressure Gage flickering.
When I first start up it will show that I have no pressure. It sometimes do it (but only for a quick second)
But today I noticed that when I hit my brakes hard the Gage will read zero for. Quick second until my truck levels at the stop then will go back to normal. then I brake slow I don't have the problem.
When I checked the oil level I noticed that it's on the low line and dirty. Could it just be that when I hit the brakes so hard that the little oil in the pan is pushed up front and for a quick second the pick up tube will have no oil? Will find out tomorrow

Hollywood...
You running gas or diesel...?

Gas v10

Found the problem oil was low. Did the change and all is good. There was very little oil in it and there was not enough for the pick up tube to have a constant feed. Good to know if I ever have an low oil problem

OK...
Continue w/ a complete fluid swap (engine oil w/ flush, transmission fluid, differential fluid). If the light still continues to flicker... I suggest purchasing a diagnostic code machine to plug into your rig... see if the vehicle's computer is spitting out trouble codes.

MWD

ooops !

You beat my by 5 minutes... glad your rig is back up and running properly

MWD