Yesterday i noticed some coolant loss which is now being looked into at the shop.

this got me thinking about what to do should the engine overheat for whatever reason. I've been told that just pulling over and letting it idle will allow the engine to cool down and that the worst thing you can do with any overheated diesel ( ie warped heads, etc) is shut it down right away. Can't seem ti find any confirmation on the net. Is this correct advice or not?

thanks in advance for your input.
John