Turbo
 

Alright my buddy is trying to tell me I dont need to let my turbo cool down. But everyone ive talked to says I need to. What do yall think?

Oil in the turbo can coke after continual shut downs over 400* EGT.

yessir, and another thing is that when you shut your engine down, there is no more oil going to the turbo. So the turbo continues to spin for up to a minute after you shut her down with no oil being supplied to it. If you let it idle between one and two minutes, to slow it down and cool it down then it will lead to much longer turbo life than if you were to just park it and shut it down. On the other hand, in my opinion, wouldn't let it idle for more than two minutes for cool down because your engine compartment gonna start heating 'er back up again without the airflow you would get if you were driving.

Let the EGTs drop to under 380* then shut her down. IF you don't have an EGT probe then let it idle 1-2 minutes max then shut it down. I've seen my EGTs drop as low as 275* at extended idle so "heating up" doesn't really happen.

Yeah I always wait 2 minutes before turning my truck off and when im towing I wait about 3 to 4 cause I dont have an egt probe yet. But thanks everyone

Depending on the weather, I've noticed that some easy driving (no romping on it, low RPM shifts, low boost) for the last few miles coming to the house lets her cool down to a safe temp. The turbo timer (set at 400°) rarely has to keep the truck idling after I turn the key off.

Anybody ever seen any data on the difference between dinosaur oil and synthetic when it comes to coking? Seems to me like synthetic would be less prone.