correct: even light driving before shutting down is usually sufficient to cool the rotor down and definitely extends the life. I have 268K miles on my F250 no turbo issues.Using synthetic oil and idling the motor for 30 to 60 seconds before shutdown will usually extend the life of the turbos. I never shutdown after using full boost without staying off boost for a few minutes. I just take it easy when I am getting close to a destinatio.pn