Whenever i slow down / stop my oil pressure gauge drops to zero, it started happening after the oil was changed. I have no idea on this one.

 

This may seem like a stupid question but it begs to be asked... Did you put enough oil in it?

 

Even further, how are your pressures reading at idle and under load? Are they within spec?

If all is good then my bet would be you tweaked the Oil Pressure Sending Unit while spinning off and on the Oil Filter and somehow damaged it internally (or pulled on the wiring) causing it to fault. After all they are right on top of each other... assuming of course you have the 4.0.

 

yeah bro,
I think the normal op PSI is around 15-55.. That idle to hwy speeds.

 

After checking your oil, clean the oil pressure sending unit. Mine had a similar problem that cleaning cured.

 

I make a habit of unplugging from the sending unit when changing the oil. On my last change it appeared that the plug was oily inside, so I cleaned it thoroughly. Some time later I noticed my oi pressure dropping and a bit erratic, so I checked and found it oily again, but only on the inside. I surmised that the sending unit was leaking, and replaced it. Voila! oil pressure is back.

 

What brand of oil filter did you use? Is it orange by any chance?

 

The fact that it started happening after changing your oil is probably no coincidence. The sending unit that controls the oil pressure gauge can be damaged during the oil change process.

Check the connector for damage. Replace the sending unit if none found. Use one purchased directly from Jeep for the best reliability/accuracy/mating with your factory gauge.

The spec for oil pressure at HOT idle for the 4.0 is "not less than 13 psi".

Or you could verify your pressure with a "mechanical" oil pressure gauge. Can be rented from many big box parts stores inexpensively.

 

it makes sense now, my dad had a good deal on a company to change the oil, and it was right after that, that it started going crazy on me. thanks for the help.

 

i have no idea, i wasn't the one that changed the oil last on my jeep, ill never let that happen again!