Dual Battery Install Complete!

[RET2]

The starter and alternator are connected to your starting battery. You can change (rewire) so either battery is the starting battery, but the simplest way is to keep the factory location as your starting battery, and have the new location (where the power steering pump was) be your house/auxiliary battery.

But, but that would be the easy way?

 

[CharlieS]

But, but that would be the easy way?

The other way I've seen it done is to use the battery in the auxiliary battery location as the starting battery, by rerouting the + loads over to the battery on the us passenger side. I guess the idea is to have the larger battery in the stock location handle the house loads. I haven't tried doing that myself.

 

[sdnative]

The largest battery that will fit nicely on the PS without extensive modification is a group 35. You can fit a group 31 on the DS. The group 35 can be used as a starting battery in warmer climates.

 

[CharlieS]

The largest battery that will fit nicely on the PS without extensive modification is a group 35. You can fit a group 31 on the DS. The group 35 can be used as a starting battery in warmer climates.

Yes, that is the combination I have.

 

[dkiogora]

Can you use a 35 battery as the second battery and still retain the Toyota battery for cranking or do you need to replace both?