PSA: That old trucker I met at a Pilot in Ohio told me to stop idling my 7.3 for 20 minutes before shutting it down

He said letting it cool down for 3-5 minutes after a hard pull is plenty, anything past that just wastes fuel and wears the glow plugs faster, and he's been hauling freight since the 80s, has anyone else heard different from their mechanic?

2 comments

2 Comments

leo6121mo ago

You ever actually check your oil temp vs coolant temp after a hard pull? The 7.3 holds heat in the oil way longer than people think, so cutting the idle short means that hot oil just sits in the turbo bearings while everything cools down unevenly. I get that fuel isn't free, but 3-5 minutes after a normal drive is one thing, after towing heavy uphill it's a different story. Glow plugs don't really wear from idling either, they only cycle when the engine is cold anyway. I've seen too many turbos go bad from people shutting down hot, and that repair is way more expensive than a few extra minutes of idle time.

the_max1mo ago

Good point about the oil heat soaking the turbo, seen a few friends learn that the hard way.