Stupid question - I've just never done it.

If I'm giving a jump:

Assume I hook positive and negative cables to the respective terminals of one of the two batteries. The alternative would be hooking positive cable to one battery and negative cable to the other battery, or does that make 24 volts? I'm also assuming if it is just the one battery, it does not matter which one you jump from?

If I'm receiving a jump:

I assume positive cable to positive post of one battery and negative cable to a good ground under the hood somewhere? Again, does it matter which battery I use? I wonder where a good ground is on this crowded diesel engine and aluminum body. Front radiator supports?

Thanks in advance.

 

No, the batteries are in parallel. You will only get 12 volts hooking up to Positive on one battery and Negative on other battery.

Yes, receiving a jump, you should connect Positive to the battery and the Negative to a good ground. You can use the bumper as a good ground. Always hook Positive first then the Negative.

 

Thanks. Basically what I thought.

 

At one time, Ford manual said this:

JUMP STARTING YOUR VEHICLE
The 6.7 diesel engine can be jump started using the same procedure as a
gasoline engine. Use the primary battery (battery located on the
passenger side) for any jump starting procedure and refer to your
Owner’s Guide for the proper method of jump starting.

I believe that no battery is specified in the manual for late models.

 

Using the primary battery just means less cable length is involved. Most jumper cables are a lot smaller than the primary wire in the truck though, so it probably doesn't make much difference.

 

Thanks. The batteries are both equidistant now on the 2017.

 

I have jumped people off using either battery. But I turn off my radio and hvac. Not that I needed too but just I case.


I usually jump off with my truck off too. I have massive cables that are all cooper and will jump even the deadest of batteries.

 

THIS.
Always leave the the vehicle giving the jump off. While manufacturers have come a long ways, vehicles electronics are not immune to voltage spikes caused by a second alternator coming to life and seeing a dead battery....

 

A lot of guys will turn on the headlights of the donor vehicle during a jumpstart, the idea being to absorb any spike at the moment the cables are removed from the dead rig.

 

It's probably a valid point, but I've jump-started vehicles for years and always left the vehicle giving the jump running. In fact, sometimes had to rev the jumping vehicle's engine a bit to provide enough juice. Never had an issue.

 

I took out an alternator on a car once, $301 lesson learned.

 

reving the to push enough juice to the dead battery is because of small cables. Buy a good set and you won't have too.


Like this:
https://www.amazon.com/Energizer-1-G...+jumper+cables

 

American vehicles are most tolerant of it. German.....well....

If the dead soldier won't fire with the good vehicle at first, go ahead and start it, take a coffee break, then shut off and repeat. I'd almost expect to have to do that if our trucks were dead and being started by a lessor vehicle.

 

Believe me, I've blown a few OVP relays in our previous Mercedes vehicles. Rather annoying.

 

I would look for copper cables, rather than aluminum ones like the referenced set. Copper is about twice as conductive as aluminum making #1 aluminum about the same as #3 copper. But #1 cable is at least better than the department store set which can be as small as #8.