Offroad-Express

Been having troubles i think with oil pressure, been through 2 oil pressure switches in a month..New switch the oil pressure seems okay and after a couple of weeks the light starts to flicker ans eventually stay on, Is it possible i am buying dud pressure switches ? I hooked up a manual gauge tonight and hot oil pressure at idle was around 35psi and not sure top side as gauge only went to 80 and it went past that at around 2500rpm, any ideas people ?

I don't know diesels but I would have thought 80psi when hot is too high....

80psi when cold would not be uncommon but hot should be 40ish??

Those switchs on the 4m40's are prone to leaking, get a straight banjo fitting bolt and remove the switch, leave aftermarket gauge in, some aftermarket switches fail quick some dont cant tell ya why bt they do.