My 2005 F250 with dual batteries sits quite a bit and I would like to put a trickle charger on it but don't know what implications the dual battery set up causes. Any thoughts?

 

No implications. Think of it as one big battery.

 

Even a Battery Tender Junior will work..

 

Yep we use Jr's on 2 and 4 battery systems, works great.

 

thanks guys. Just wasn't sure, now I know.

 

Just a note. With a Battery Tender, the ring terminals you can put on the battery, are only 23" long. Fine for a pre '08 where the batteries sit crossways in the truck. You can install them and run the cord out and zip tie the quick connect to the grille. On '08-'10s the batteries are sideways and the connector is too short. I had to get an extension for it. Only problem is, it was 12.5' long

 

oops, are you saying both batteries have to be hooked to the charger at the same time?

 

No. Just one set of ring terminals on one battery. They are hooked together. Charge one, you charge both.

 

In a standard van, I'm not sure what purpose the Aux battery would serve?

In my RV, there is an engine battery, and there is the Aux battery (house battery).

On the dash, there is a 3-way rocker switch. To the right, you have to hold it down with your finger. This temporarily (while pressed) gangs the house battery to the engine battery so that you can start the engine from your house battery if your engine battery is dead. It's an emergency start battery in that case.

In the center position, the house and engine batteries are isolated from one another.

In the left position, the alternator can charge the house battery when the engine is running. But, the flow is one-directional - the house battery gets charged but does not contribute to the engine side of the system.

Since the house battery is designed for deep cycling, a deep cycle or a Marine battery is good. Deep cycle batteries have thicker plates designed to provide relatively low current for longer periods of time. Regular starting batteries generally have more porous plates designed to provide high current for short periods of time (starting an engine). Starting batteries do not tolerate deep cycling as well or for as long as deep cycle or Marine batteries. Marine batteries are generally a compromise between true deep cycle and starting batteries. But, they are generally cheaper and more readily available than true deep cycle batteries.

In your van, what runs off of the aux battery? Anything? Or is it just a reserve battery for starting the engine?

Steve