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Thread: 1990 F150 300-6 oil pressure

  1. #1
    Join Date
    Nov 2008

    Default 1990 F150 300-6 oil pressure

    I have good oil pressure at an idle but the oil pressure completely drops out at RPMs above 1500. The oil pump was replaced 2 years ago. When the oil pressure drops it goes from 35-40 psi to 0 and you can hears the valves start ticking. I am a Chevy guy struggling with this Ford and have never had this problem in any other truck.

  2. #2
    Join Date
    Jan 2007


    TexasFord - Try changing the oil filter with a new one it sounds like the filter is bad. If your not that lucky then you may have a bad pump, plugged oil pick-up screen, bearings that are bad or even a plugged oil journal. I hope it just the filter.

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