After engine warms up oil pressure drops to 0 at idle. on 2001 Dodge Ram 2500

It goes back up to about 28 lbs when rpm reaches 1000 or more.

2 answers 1 comment
Check your oil level.It sounds like the oil pump is going bad.
Oil level is full. No gas smell in oil
I had a 1995 DODGE RAM 1500 with a 318 c.i.d. engine that did something similar,If oil level is ok. , and there is no knocking or tapping, Try another oil press. switch .There not that expensive but they are a bit of a pain to get to......back around the distributor.If memory serves me right i think you may need a special socket to remove the switch. Good luck