80+ PSI oil pressure?

So I finally got my 1987 Dodge Ram 50 2.0 running with the help of a Weber conversion kit. Now I am poking around to make sure I didn't buy a turd.

I noticed the oil light came on which alarmed me. It stayed on no matter the engine conditions. This alarmed me because these oil pressure switches only close at absurdly low psi so I removed it and connected an actual oil pressure gauge. It was pushing over 80 psi. This is a gauge I've used before and trust to be accurate. The motor has 170000 miles on it. I only checked it cold. I will check it warm tomorrow when I get to the shop.

The oil light was on before I changed the oil as well. I couldn't find any specific oil weight for this truck so I checked on ALLDATA and it specified 20w50 for my climate (north Florida). This seems very heavy to me, but I don't know enough about these engines to challenge what ALLDATA says. There does not seem to be a flow issue because I can see the oil splashing around all over in the valve cover.


I have two questions: What oil pressure is your 2.0 pushing? And what oil weight should I be running?

20W50 would be for the Diesel engines, 10W30 should be fine for your engine. Yeah I can see it hitting 80 psi with 20W50 cold, you probably killed the oil pressure switch with to much pressure.

The shop manual says under 2.0 engine specs....80 kPa (with is metric) or 11.4 PSI

Cold pressure is totally normal that high.