This turbo timer allows you to choose how long you want the truck to idle for after you leave it and turn it off.  It can idle for either 30 seconds, 1,2,3,4 or 5 minutes after you leave to allow the turbo to drop down below 300 degree F which allows the turbo to last much longer with little problems. 

Here is a picture of the timer.  It is a plug and play device from Bossard in Australia.  This is the outfit he bought it from who successfully shipped it here to the states in less than a week.