BY JIM BIGLEY
HOT/COLD DURAMAX OPERATION
I recently bought a used 2007 GMC equipped with the Duramax, and I have a few questions concerning cold starting and turning off the engine. I live in northeastern Montana, so it can get pretty cold during the winter. I’ve been told that I should consider plugging in the engine block heater whenever the overnight low dips below +20 degrees F. So, my question is: how long should I let the engine warm up in those conditions before starting? Is engine warm-up as important during the summer months? Also, what is the appropriate cool down for the turbo before shutting the engine off? One mechanic says wait 5-7 minutes. Another says I can shut it off right away. I heard the turbo can bake the oil in its bearing assembly if not allowed to cool down properly. Please help a new diesel owner. Thank you for a great magazine!