I try to idle my engine as little as possible, but sometimes I have to. I've heard that Paccar engines should be idled at 800-1,000 rpm to get oil to the top of the engine. Is this true in all cases? Let's say I'm idling with the a/c on for an hour, should I increase the rpm? I have a 2021 T680 with a 510 MX13 Paccar engine and Paccar transmission. Thank y'all for any feedback!