4.0 Reading Low oil pressure??

It seems like every time i'm waiting at a light, or just in Park sitting and idling, the low pressure warning light comes on and my gauge is reading zero.
I just got the oil changed today, so i'm not sure it the overall oil level was low or what. But this warning light was coming on a lot trhis past week, and over the life of the vehicle it would seem to come on sporadically.
Most notably when i've been out wheeling.

Is this a sign that there's a problem a-brewin?? :farmer:

First thing I would do is check the oil level...if it is low enough it might cause something like that to happen...or maybe your gauge is a little off

What brand oil filter are you using?

I just got the oil changed today and didn't check the type of filter.
They added the right amount of fluid though, 5.7 litres, so that's not the issue. Unless of course it was pretty low before, in which case i shouldn't see the problem this week.

Thing is, i've ALWAYS had this occur, for the full 4 years i've owned this Jeep. The pressure gauge will drop a bit when stopped at a light or idling. It doesn't go all the way to the left, but it will often be at the 1/4 mark level. Then i accelerate and it goes back up to the halfway mark.

The Adam Blaster said:

The pressure gauge will drop a bit when stopped at a light or idling. It doesn't go all the way to the left, but it will often be at the 1/4 mark level. Then i accelerate and it goes back up to the halfway mark.

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Normal. I really took a notice to this on mine when I started running hot one day and looked at the oil pressure and it was extremely low.

Except in the dead of winter, i run 10W-30 as it is a bit thicker.
I have noticed when wheeling i will run a bit hotter than normal. And i usually see the low pressure.
So, is this whole effect just the engine running a bit hot and then thinning out the oil resulting in a lower pressure reading?

I am a newbie BUT! I would have the oil pressure drop to zero so i figured it was the sending unit.... nope so next I took off the pan to swap out the oil pump and HOLY CRAP! The bottom of my pan was filled with burnt up oil (looked like charcoal). It was so deep the it was cloging the screen on the oil pump.
These 4.0 are killer. If I ran my Nissan truck with almost no oil I would be shopping for a new motor.
So that you don't think I did this to my Jeep, I had just got it for free from a friend after it sat for three years.


bill