Throw a sheet of plywood down on the floor of your truck and make it flat!
This will help you out by:
- Makes a flat surface to slide things.
- Protects your knees (those ridges can hurt if you need to grab something real low or just work on the floor).
- Makes a sacrificial layer. Some dudes lay down two layers of plywood. The upper layer is sacrificial and can be swapped out once it gets beat up or oily.