Is it normal to have no oil pressure right when I start my truck up? 00' Ford Ranger?

[Aliensxist]

Normally in the summer the second I start my truck, the oil pressure gauge pops up into the normal state. However, I've been having an incident when starting my vehicle lately. Immediately when I start it, the oil pressure gauge stays at 0 pressure (red line) and stays there for a good minute or two (or until I reach about 20mph or so...) The engine doesn't seem to be making any clunking sounds when Idling or even giving gas, and there are no oil pressure lights turned on, so I decided the first time to start driving with it like that. It drives normally as such, and when I get to main road speeds, the pressure gauge pops up into the normal. The vehicle is a 2000 Ford Ranger, and still has another 100 miles or so before the next oil change is "due." I checked the Oil and it seems to be good, and it doesn't burn oil.
Is this normal for the colder weather???
I'm guessing it's the colder winter weather (live in Phoenix so it's about 40f-50f tops) making so the oil is more dense and takes a little bit more time for the oil to circulate to all parts of the engine??? But I have no idea...

 

[BRIGGS]

no oil pressure is bad period. I would recommend getting a pressure gage tool and connecting it to the engine then finding out if there is oil pressure or if there is a problem with the gauge. Keep in mind most engines will run for a while without oil, however damage is being done. If upon using the pressure gauge you confirm the pressure is low have the pump serviced immediately, also blow out all the oil journals.

Now to be completely honest if you know you've been driving without oil pressure for any period of time expect that there will be some damage to the crank bearings etc.

if you find the pressure if normal (you can probably rent a pressure gauge at autozone and hook it up to the oil pressure sensor. Compare your reading to the truck specs.) If you are in range then replace the dash gauge.