Just a question about oil pressure. I have a 94 f150 with 5.8L. I don’t really understand the oil pressure. In the morning, especially when it’s cold, the oil pressure is low, and once the engine starts to warm the pressure starts to go up. I understand that the factory gage is not accurate, but this is backwards from every other car I have ever had. Is this common or something weird?

 

For your complaint I would not worry about it, as long as when the key is on and the engine is off the cluster indicates low oil pressure and when the engine is on it indicates oil pressure present.
I really hate that ford uses a gauge for oil pressure, it makes people think they are looking at oil level which it absolutely is not.
Oil pressure switches are similar to a door ajar switch, it cannot tell you how far open the door is, merely that it is not closed, all that a oil pressure switch tells you that there is oil pressure, you can get awful damn low on oil level before this light comes on though, its more a warning to turn off the engine or you will cause internal damage.
Here is the oil pressure switch on the electrical diagram, as you can see all it does it close the circuit when there is oil pressure and open when there is no oil pressure, there is no in between, it does not have a electrical potentiometer like a fuel level sensor or how the resistance of a engine coolant temp sensor change as the engine/sensor gets hotter and the module knows what resistance equals what temp.

 

The dash gauge is basically an idiot gauge which will deflect into normal with around 6-7 psi of pressure. The oil pressure switch will work or won't work as it is a switch. Your dash gauge likely is behaving strangely. You may want to install a good aftermarket electrical oil pressure gauge in your cab. Don't consider a mechanical oil pressure gauge.

 

The original gauge is a fake, but it's very easy to make it work - just install a pre-1986 oil pressure SENDER on some plumbing to move it away from the block (because it's physically larger than the 6psi switch), and solder a jumper wire across the resistor on the back of the instrument cluster close to the oil gauge terminals. Click these & read their captions:

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If you ONLY want to make the needle steady again, you probably need to crimp the barrel connector on the switch slightly tighter. If that doesn't fix it, clean the instrument cluster terminals with brown paper or a pink eraser back to shiny Copper on the film circuit, and shiny metal on the harness terminals.

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This level of disassembly is not necessary, but it allows thorough cleaning of 3 decades of dust out of the cluster:

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This explains how to remove the cluster:

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Be gentle with the black cluster bezel, and the trim strips - they're VERY fragile at this age (especially the screw holes for the fuel tank & ESOF switches), and not easy to find new.

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If it has a white tube for the shift indicator, that's extremely fragile, too.

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So is Albert Waldridge Oil pressure gauge a mechanical gauge with a physical needle that moves or is it like Kozal01 digitally animated gauge?
If it's a mechanical gauge, some times they don't have a spring return to zero or they stick and don't fully return to zero when powered off. There are gauges that use a magnetic field to position the pointer, like some of the old gas gauges, when you turn the power off, the needle just rests in the last place it was at. I guess we need a picture.

 

Digital slider light. I understand it is a "dummy" light that only shows oil pressure is present. The concern i have is that it shows pressure KOEO (Key On Engine Off) state. Wanting to be certain if in an oil pressure failure event that I would get an alarm.
I guess I could install a shutoff valve inline with the sensor and see how it reacts, or a trip to the dealer since still under warranty.

 

It is not a gauge, only a "dummy" light. My complaint/concern is that it shows pressure at KOEO

 

I agree this is backwards that what is expected. When the oil is cold, the viscosity is higher causing resistance to flow, which results in higher pressures. When the oil heats up, the viscosity lowers thus creating lower resistance which means lower pressure.
As to your question, has the sending unit been replaced? maybe a reverse acting sending unit has been installed not matched to your gauge. Also wiring may be reversed, but that depends on the type of gauge and sending unit configuration/type.