Forum Discussion

GoFish's avatar
GoFish
Explorer
Jul 28, 2014

Charging the camper batteries with the truck motor

I have not been able to get a good charge to the camper house batteries using the truck alternator. I have the dual 105 amp alternator option on my 2004 Duramax for total of 210 amps of potential outp...
Truck Campers
DiploStrat's avatar
DiploStrat
Explorer
Jul 29, 2014
wintersun wrote:
All that is needed for the short run from the engine compartment to the receptacle in the bed of the truck is 8ga wiring for the power and ground lines. You can use thicker gauge but it is not going to make a measureable difference in charge times.

You may also have a failing alterntor with your truck. Easy to get it checked out in terms of output. Second component that can cause problems is the voltage regulator. Third possibility is a failing battery in the camper or in the truck. A bad cell creates added resistance in the circuit.


With deepest respect, that is incorrect. Going from a AWG 8 wire to one that is properly sized for for the load will dramatically increase the charge rate and reduce the time required.

An 8 AWG is about 8.4mm2. I run a pair of 1/0 AWG cables, call it 53mm2 each or over 100mm2. Trust me 100mm2 of cable will charge your battery much faster, even 20 feet away.

Your comments about the possibility of a failing alternator or regulator are, of course, correct, but even assuming that his alternator regulator is perfect, an 8 AWG cable will only carry about 50A 10 feet, round trip.

About Travel Trailer Group

44,027 PostsLatest Activity: Mar 05, 2025