2000 f100 help needed

[beenfishin21]

I have a 2000 f100. After running at above 5500 rpm for more than about 10 minutes and backing off to an idle, the oil alarm will sound. If I adjust the idle up to 1200 rpm the alarm will rarley sound.

 

[MIDNIGHT EXPRESS]

oem filter/proper oil wt/faulty oil pressure switch/ i beleave the switch works off resistence bad wireing or conections??? you might ck this sight on cost to try new oil pressure switch however parts changing is not my first choice hope someone can help with specs to test first a manual gauge will help you determin if oil pressure is low for you yamaha guys where can a manual gauge connect to the engine block?