Now that you know how to jump-start a diesel truck with two batteries, you’ll know just what to do when someone else needs your help.Ĭheck out all the battery cables available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. Keep those jumper cables handy, just in case. Take your truck for a drive, and try not to shut off the engine for at least 20 minutes. Remember to let your revived truck run for a bit, allowing the alternator to put power back into both batteries. Stay careful and alert until the clamps are detached from any batteries to avoid electric shock or fire.
Start the engine of the vehicle with the good battery, and let it run for a few minutes.Find a piece of unpainted metal on the vehicle you’re jumping (the alternator bracket is a great choice), and connect the last black cable’s clamp to it.Connect one of the black cable’s clamps to the good battery’s negative terminal.Connect the cable’s second clamp to the good battery’s positive terminal.The terminal will either have a “+” symbol or a red cover. Connect one clamp of the red jumper cables to the positive terminal of the dead battery.
Turn off lights and other accessories in the vehicle you’re jump-starting.Put both vehicles in either “park” (automatic transmission) or “neutral” (manual transmission).Once you get the engine started, the alternator will do its job, sending a charge back into both batteries, even at idle. This means you can jump-start your diesel engine by connecting to just one of the batteries - usually the most accessible - in your vehicle’s engine compartment. The batteries in your truck are in parallel. Luckily, you don’t need to find a friendly stranger with a dual-battery vehicle in order to get yours moving again. How Do I Jump-Start a Diesel Truck With Two Batteries? It simply takes more oomph to fire up a diesel. Compression ratios for diesel engines are almost twice those of gasoline engines. The dual-battery setup cranks extra power that can overcome the higher resistance of a diesel engine. It’s not uncommon for diesel trucks to have two batteries. Avoid getting towed or stranded by learning how to jump-start a diesel truck with two batteries. The upsides of a diesel truck are tons of torque, rugged construction, reliability and long life. If you recently bought a diesel truck, you’ve made a smart move.