Thanks, I will go out and see if it has a readout for EGTs. I thought it was more of a hot oil "coking" up the turbo. But I know absolutely nothing about nothing. That's why I ask.
Hot oil "coking" was a problem before most turbos had water cooling jackets around the compressor bearing. The bearing had only oil, used for lube and cooling. With a high load, the compressor spins at a high RPM (125,000 - 200,000 rpm).
When you shut the engine off too soon after a high load the the heat that is already soaking the turbo is increased while the compressor was still spinning, without the benefit of oil circulating. So, the heat would cause the oil to "coke", eventually clogging the passage and wiping out the bearing.
Your modern truck diesel has a water cooled "wet" turbo.
Under normal driving you really don't need a cool down period. That doesn't mean that I would just shut the truck off after giving it some throttle into your final destination (my last 1/3 mile home is all uphill).
Towing the trailer I would let it run for a minute or two after stopping. Another reason for an auxiliary tank, I almost never stop for fuel with the trailer. And getting into camp, by the time you are unhooked it is a moot point.
That said, I have a timer on my truck, it is set for about 2.5 minutes. About half the time I let the timer shut the truck off, the rest of the time I will idle for 10 seconds or so then shut it off manually (stepping on the brake)
