There’s no real secret to keeping your diesel truck performing at its best. Like all other internal combustion engines, they operate most efficiently if they have these three things: Air, fuel, and lubrication.
A clean air filter keeps dirt out of your engine, as the intake will pull air into the airbox with tremendous velocity. Factory air filters are more than adequate, but some prefer an aftermarket filter. Keep in mind that an aftermarket filter will also need servicing or replacement on a regular schedule.
Diesels have many more bearings internally, and most use a turbocharger for additional power. This means you need clean, fresh oil for lubrication, and a clean new filter to go with it. A clean engine will last much longer than an engine that is exposed to dirt, condensation, or metal shavings from wear.
Fuel is critical to diesels, as the quality of the fuel has a direct effect on power generation. Make sure you buy your fuel from a reliable station, and change your fuel filters as outlined in your maintenance schedule.
Do these things, and your diesel will perform well and have a long service life.