Low oil pressure at start
Live in California have 320,000 miles on truck am
getting 20 lbs at cold start looking for a reason.
320,000 miles of wear all tolerances have enlarged, in addtion the oil pump has worn that's why only 20Lbs of PSI.
Does it stay at 20 lbs or does it drop as it warms up? If it drops the engine has excessive clearances in the bearings, if it doesn't drop then the possible cause would be a stuck oil pump bypass valve, it is stuck in the bypass position. HTH
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