 At Hot Shot Secret, we share the science behind common diesel problems. For example, ultra-low sulfur fuels. Fuel has two purposes, combustion and lubrication. Ultra-low sulfur fuels have diminished the fuel's ability to lubricate. Hot Shot Secret everyday diesel treatment with LX4 restores lubricity, protects your engine, and optimizes performance. Everyday diesel treatment is available at truck stops, tractor supply, O'Reilly's Auto Parts, and online at hotshotsecret.com. Hot Shot Secret. Hold.