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...
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