4.0L ,318 or 360 V8?
I would say you have good oil pressure if the needle is in the center or just above. the pressure needle should not be all the way to the left or right.
cold, idling, most V-8s should be around 30 lbs. Hot, idling, about 20. Usually maximum on a V-8 is about 60 lbs, unless you have a high pressure or high performance oil pump installed. Then you can get 80 lbs of pressure maximum... Most V-6 and 4's average about 5 lbs less across the scale...
I had my oil changed at the dealership yesterday and this morningthere was two spots. I have a 2013 Jeep Grand Cherokee and the oil pressure is reading at 38 to 45. temp 171 to 181
If you have a 4.0 jeep engine and having oil pressure problems here what your issue is! The 4.0 cylinder head is extremely bad about cracking across the top of the head near the rocker arm towers. It allows coolant to seep over time and sludge the oil causing low oil pressure at idle around zero and higher pressure while driving. I just pulled my engine to rebuild it and the oil looked like sea weed. The machine shop I use all the time said the 4.0 heads crack all the time. I found a company the remanufactured new heads that are stronger and thicker where they crack all the time. Go to my website send me an email and I'll give you there info. bigasautorepair.com just click on contact us. Hope this helps!
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