Having problems with your 1998 Dodge Ram 1500 4WD ?
Oil pressure drops to zero after a few mins of running.
Assuming that you have checked the oil pressure sending unit and it is working properly. I would check the oil pickup inside the oil sump. It sits very close to the bottom. The way the oil drain bung is made (the treads go up into the sump) doesn't allow all of the oil to drain out when changing the oil. So, any gunk that builds up in the bottom, like metal shavings, etc doesn't drain out when changing the oil. It can be picked up by the oil pickup and that is what can cause it to loose oil pressure. The filter should catch the gunk before it makes it to the engine. But if the oil filter becomes plugged up, it will bypass the filter and it will travel to the engine.
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