Jumping truck battery from small-ish car

[robert]

Friend’s son has a full-size Dodge truck that appears to have a dead/dying battery — (lives in another town).

It’s been suggested that he shouldn’t jump his truck from his girl friend’s Corolla. Difference in electrical system could harm Corolla.

I’ve never heard such a thing… But, it’s possible. So, this is a reality check. >>> QUESTION: If done safely, as prescribed by the pros … is it safe to jump truck to car, or not?

Okay pros, please weigh in.

Topic

[DEVEN PRASAD]

It should be fine as-long as the amperage draw of the trucks starter motor does not exceed the Cranking Amps of the Donor Battery.

A issue that could arise is that the Truck draws too much current, which would cause a voltage drop on the donor car side, and this can cause issues.

[Andrew Webb]

If the truck is stranded somewhere, then jumping it, either from a car or any vehicle is the only option. I would suggest that if you are trying to jump with the small car, and are getting no where with it (for example the vehicles are hooked up for several minutes) and you are getting no results, I would stop to avoid causing any electrical system damage or physical harm.

The best solution would be in the event that the pickup truck is parked at your friend’s house. A battery charger is the better option. Jumping a battery does get the vehicle started (in most cases) however a common mis-conception is that the alternator will recharge the battery after driving it a while. All the alternator will do is keep the battery at its current charge after it was jumped.

With that being said, give the battery a slow charge overnight, but no more than 10 hours I would say. Also, if you see the battery charger’s meter bouncing back and forth, that is a good indicator that the battery itself is no good.

Good luck!

[zero]

[quote=”andrewwebb58″ post=126168]The best solution would be in the event that the pickup truck is parked at your friend’s house. A battery charger is the better option. Jumping a battery does get the vehicle started (in most cases) however a common mis-conception is that the alternator will recharge the battery after driving it a while.[/quote]

True as day. Alternators are not chargers they are charge maintainers. Ever noticed how if one goes, the other is not far behind? That’s because the battery will start to fail and the alternator will have to work overtime to keep the battery charge state. Thus leading to early failure.

Anyway you look at it, buying a cheap charger is cheaper than replacing electrical components on another vehicle. Boost down in size, not up.

[robert]

The truck owner is totally nonmechanical and he’s located in a different town.

My advice to them was, take the battery it into O’Reilly’s. They will fully charge and test it for free. Then they can go from there. That eliminates the voltage issue entirely.

Of course, that comes after questions regarding are the cables clean, was a light or something left on, was is showing signs of starting hard/slowly before, etc.

Agree, owning a battery charger is pretty much a must…. I think.

Since initial post, I’ve poked a bit online and found that some gasoline truck engines run 12 and 16, sometimes 24 volt system. And diesels (not in this case) often run 24 volt systems.

That’s good to know for the future, just in case.

Thanks for the insights and thinks.

[Lorrin Barth]

I’m trying to figure out the difference between maintaining and charging. They both sound like charging to me.

If I have a flat battery I won’t connect a battery charger until the battery cables are disconnected. Actually, I will pull the battery y out of the vehicle to make sure no accidents occur. My car has five computers and the idea of replacing them and associated wiring is not appealing.

While I know it is a common practice I suggest that jumping vehicles should not be done. There is just too much at risk. In an older vehicle the cost of repairing electrical damage can quickly exceed the value of the vehicle.

[Author]

Replies