How To Charge A Diesel Truck With 2 Batteries. Be sure both batteries are at full charge before doing this. And plugged a trickle charger into it and pluged the block heater into it put the charger on one battery and had the plug for this hanging out the grill.
Jumper the two negative posts and the two positive battery posts together than hook up the trickle charger to one battery. How to Jump Start a Diesel Truck with Two Batteries. Disconnect each battery and remove them from the truck and charge each one separately 3.
If both cable thickness is the same either battery can be jumped.
If you need to charge simply connect a battery charger to one of the batteries and plug it in. Lets get into the nitty-gritty. The thicker cables will be the battery you connect the jumper cables to. If you have two batteries in parallel you would disconnect the ground cable of the other battery before touching the positive cable on the first battery.
