Low oil pressure 25psi 40psi cold.
25 to 40 cold is not that bad, does the oil pressure increase as it warms up?
25 warm 40 cold
Sounds like a stuck oil pressure bypass valve, verify the oil pressures using a manual gauge, if it confirms the low readings then replace the oil pump and pickup screen.
25 psi at idle when warm isn't low
My Yukon idles at 40 lbs warm.
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