I have a 2003 Durango with the 4.7 V8. Recently the oil pressure gage got to where you first started the vehicle, the gage did not come up, and you got the light "Check Gages". You could turn the ignition off and restart the car and it would be all right. This did not happen all the time only when it was cool in the morning. If the outside temp was above 90 degrees, it always worked just fine. So I picked up a sensor from the local automotive supply place and after buying a special socket changed the sensor. Well it worked okay for a day or two and it when to zero again and the idiot light came on. Their is no audible sound of no oil pressure. There are no TSB's on the 4.7 engine for the 2003 Durango, and I've used nothing but 5W30 synthetic oil for the 135,000 miles that on it, and changed every 5,000 miles. Does it sound like a bad sensor?

 

You most likely have a bad anti-siphon valve in the oil filter or the anti-siphon valve is not installed. Change the oil and get a filter (I like OEM Mopar Filters you can get em at Wal-mart $5) or what you like. Just make sure they have a anti-siphon valve built in it.

If the oil siphons back to the oil pan it needs to re-charge all the way up to the filter and push the air out before making it to the bearings then to the sending unit to show the pressure. When you start it and it starts the process, then you are turning it off then back on which gives it enough time to finish the process (Prime the Oil Filter). Also, most likely you can hear the valves chatter from loss of oil during the first starting.

 

I noticed after posting the thread a spot of oil under my Durango. It has never leaked any fluids in a 135,000 miles so I investigated the problem. Seem the new Oil Pressure Sensor I had installed was bad and leaking internally and it took a couple of days for the oil to make its way out through the connector, and finally dripping on the garage floor. So I replaced it with one from the local dealer and everything is okay. What was also shocking was the one from the dealer was cheaper in cost that the one I picked up at a local auto parts store.

 

Thanks for the update. I can honestly tell you I have NEVER heard of that before. I like to use dealer parts as well and it goes to show that you need to check around to find good prices.