Yeah that's interesting that a new guy shows up and isn't just questioning one of the more seasoned members but essentially saying he doesn't know what he is talking about.
The following is taken directly out of the INTERNATIONAL® VT 365 DIESEL ENGINE 2004-2006 Model Years EGES-295-2 Service manual. I will let you be the judge as to what you think it means.
The VGT increases power output by supplying
compressed air to the engine. The internal
components are oil and air cooled. Engine oil is
circulated through the housing, which acts as a
heat barrier between the “hot” turbine and the “cold”
compressor. Sleeve Bearings are lubricated by
engine oil. Oil is pumped directly from the oil filter
base, circulates to the VGT housing, and returns
to the sump through an oil drain in the VGT center
Lube oil moves through
passages in the crankcase to lubricate all internal
components and to supply the piston cooling tubes
and high pressure pump reservoir. The VGT and air
compressor use external oil lines.
The oil filter base directs filtered oil in four ways:
• One passage supplies filtered oil to the oil
temperature sensor, oil pressure sensor, oil
supply tube for the VGT, and oil supply for the air
Vanes mounted around the internal circumference
of the turbine housing are connected to a unison
ring. When the unison ring moves, all vanes move
to the same position. The unison ring moves, when
either side of the actuator piston receives pressurized
It seems pretty clear that the recommendation to allow one's turbo to cool off prior to shutting down the engine to prevent oil coking is solid advice, regardless of whether the oil sits there around the bearing or drains back into the pan after shutdown. Cutting off your engine (and thus your cooling system) while your turbo is excessively hot is clearly a bad idea. Installing an EGT gauge and taking steps to keep your turbo and your engine healthy is both simple and wise.
Good advice is just that.......and is generally better than bad advice....regardless of who is giving it to you.
Is this a hairy knuckled Diesel Forum? Or a bunch of delicate feelings Prius owners? Good grief.