If a diesel powered truck runs out of fuel, it will not restart after you have obtained some diesel and put it in the tank. A diesel will not pull the fuel from the tank to the engine if the fuel line is full of air. You must first prime the engine with fuel before attempting a successful restart.
Look in the owner's manual for the location of the fuel primer pump and bleed screw. The pump and screw will be located somewhere near the fuel filter on the engine. The primer pump will be a large push button, rubber bulb or small lever.
Loosen the bleed screw a couple of turns. The loose bleed screw allows the air to leave the fuel line as the fuel is pulled from the fuel tank to the fuel filter.
Pump the primer pump until diesel fuel comes out of the loose bleed screw. The primer pump is very small and your fuel line may have a lot of air, so be ready to pump for five to 10 minutes before you see fuel coming out of the bleed screw.
Tighten down the bleed screw with the screwdriver.
Attempt to start the engine normally. You may need to crank the engine for 10 to 15 seconds before it starts and runs. If the engine does not start within 15 seconds of cranking, repeat the priming process to get more fuel into the fuel filter and pump.
Most diesel truck engines have primer pumps. A few have a lift pump in the fuel tank to push fuel to the fuel filter. Check your owner's manual for how to engage the lift pump. A diesel engine needs a strong battery to crank the engine fast enough to start. If your truck has lost prime due to sitting around, check the battery charge before attempting to start the engine.
Do not forget to firmly tighten the bleed screw. You don't want to have diesel fuel leaking onto a hot, running engine.