I have a 96 2500 360 auto tranny with about 160xxx miles on it. The problem I'm having is when I slow down or I'm idling I have zero oil pressure, but when I give it gas I have normal pressure.The oil pressure sending unit has been replaced and I made sure there is enough oil in it. Any idea on what else it could be? Maybe I need a new sending unit, or I need to replace the oil pump perhaps? Any help would be great. Thanks

 

Put a mechanical gauge on it, and see what is REALLY happening.

 

^^^ +1 first thing do to is this test.

 

will do, thanks for the advice guys.