My garage has a small slope to the front of the garage for drainage, nice except my Tool Box isn't level and the drawers won't stay shut! Has anyone leveled their tool box to keep the drawers shut before?
My garage floor is not flat either. I used my car jack, a broad piece of wood and some wood shims. You may also consider what was talked about in other threads. To prevent theft of your entire box, take off a wheel or two and replace with some wood blocks.
Sloped floors ****......If the box is going to stay in one location, remove the casters and replace them with adjustable threaded feet. These are available in various capacities.