I was just wondering if it's safe to wash a diesel engine at a car/truck wash? I wash the engine of my car about once a month (I keep it spotless) but would it hurt to wash the diesel engine of a big truck? 8)

It won't hurt it. Just make sure you don't spray water into the air filter. :wink:

Be sure the engine and turbo are not hot. You could crack the block or turbo with cold water. Don't get the pressure too close to the gaskets, they could tear in towards the engine. Just apply some soap, and rinse it off.

Just make sure the wash wastewater and petroleum residue is properly disposed of. Some locales take a dim view of oily waste going into the environment untreated. BOL