I started out years ago towing our 7,000 lb trailer with my old chevy 2500 with the 350. I tow mostly in the Sierra and Rocky Mts. I hated the way I had to slow down to 45 mph going up the grades. So ...
And as soon as the motor/RPM's start pinging off of the rev limiter, and the injectors start cutting out as directed by the motor electronics, you will get the message that you were pushing just a wee nad too much. However, as stated, you cannot hurt the dang thing like I used to do on a regular basis when I was younger and big six pak carbs were the order of the day!