I've got an 03 Dakota 3.9L with 227k miles, and for the past 10-15k miles, any time I start the engine, it takes 5-10 seconds for oil pressure to build to normal levels. I just had the pump and pick-up tube replaced as a precaution, but I've got no idea what causes this or if it's normal. It does it regardless of engine temp, and once it builds, it holds firm. I know this isn't a low-toleranced engine by any stretch of the imagination, I just need to know if this is hurting the engine in the long run. This could have been happening the whole time and I just realized it 15k ago, idk. Video below.

https://photos.app.goo.gl/xAx4H1S7CCDQceqt7

 

How are you determining that the oil pressure is low? The dash gauge can be a little slow to react or the sender can just be wearing out.

Put a mechanical gauge on it and check.

 

I know the gauge is slow, as shown in the video, as it takes a about 1 second to jump into action. What concerns me is the amount of time it takes to get to operating pressure after that. It might just be the gauge, I just find it odd that that's the only gauge that does that (that being said, it's also the only pressure gauge in the cluster).

 

Sounds normal to me. The oil sits in the pan and has to be pumped around the engine when it starts. It doesn't just start instantly at full pressure. It has to build. This is the reason why you drive gently when starting off cold... the engine is not fully lubed yet.

 

Pressure in the video looks plenty strong for idle after starting IMO.