I don't know what it should be at idle, but it should read between 40-60 psi at 2000rpm. Yes, it will vary with rpm, as the engine spins faster, the oil pump moves faster, creating more pressure.
40-60 sounds right to me. I think the rule of thumb for minimum oil pressure is 10psi per 1,000rpm. From my experience engines with low OP still tend to run quite awhile if driven easy.
If you are concerned with oil pressure, make sure you check OP with a mechanical guage.
The stock electrical gauges are notoriously way off. I have had mechanical guages in everything I have owned with a 2.9 and the two gauges rarely agree. It should be around 20 at hot idle.
well at about 60-65 mph and cruising at 2500 rpm im at about 21 psi. the reading is from a aftermarket mechanical guage.. that all with 10-30w oil. bad part is it wont stay at 21 psi it goes to 0 psi at idle but if i take it out of gear it'll go to about 5 psi. no trouble with the engine on the trip to WA ran cool as hell. well except the fuel pump got hot and would quit on me. nothing a little ice couldn't handle. im going to try to run a little thicker oil 10-40w before we leave back to CA. if that dont work when we get back home im going to try 20-50w and take it from there.....
