The customer may comment that the oil pressure gauge jumps from approximately 40 lb. to 60 lb. three times within the first few minutes of driving as well when the engine revs past 3700 RPM.
The 4.3L (LV3), 5.3L (L83), 6.2L (L86) engines are equipped with a two-stage oil pump.
The oil pressure gauge jumping three times is caused by a test routine the engine goes through during the first few minutes of driving to ensure that both stages are operable.
The oil pressure gauge going to 60 lb. over 3700 RPM, is the calibrated engine speed the oil pump goes into the high-pressure stage.
No repairs should be attempted, this is normal operation for these engines.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.