Turbo blanket

[cRiPpLe_rOoStEr]

Originally Posted by Piotrsko

First gen 7.3 diesels had an idle cool off period requirement after running on the freeways both to prevent bearing coking and cooling the turbohousing.

At least until late 90s it used to be a common practice in my country, for other engines. When it comes to oil coking on the bearings, it's something I no longer hear about it, while complaints about the VGT actuators on modern turbos has been quite common nowadays.