I have a 97 suburban with 5.7 motor. I drive once a week or less. A few months ago I noticed oil pressure drop from 45lbs to 0. Only for a few seconds and then it would come right back up. Has done this for a while now. But Saturday pulling into my drive with window down I heard lifter ir rocker are clatter, looked down and 0 oil pressure. 3 or 4 seconds later back up to 45lbs but it took that long again for clatter to go away. At first I thought bad sending unit but now that I have heard clatter I think oil pump. I just have never heard of oil pump failure. Anyone else experience this?