When you appreciate safety equipment......

I think I was 15 and was doing an engine job on an old 70s U Haul with a 391 heavy duty FE truck engine. 4 speed, of course. Had the engine hoist in front with everything disconnected and jacking the engine up. I was between the hoist and the front end of the truck.

In my infinite wisdom and total inexperience, I forgot to chock the wheels or apply the parking brake.......shifter in reverse in the NP435. Soon as the engine breaks loose from the transmission, the truck starts rolling slowly backwards........pulling the engine hoist at an angle and trapping me between the hoist and front end of the truck. Luckily, one of my coworkers came running over and jumped in and stopped the truck.

No, I never made that mistake again.