Trouble With 2003 Chevy Silverado 2500 Duramax Charging Trailer Battery Bank

Question:

I have a 2003 Chevy Duramax. It is equipped with a single alternator. It has the mount for a second one, but I suspicion there is more to the electronics than simply adding another generator. My problem is simply, the truck does a very poor job of recharging the trailer batteries while driving. Alternator output is fine. I believe its a 120 amp alternator. Truck batteries are new. Battery cables are in good shape. I have power at the plug, just doesnt seem to ad much even on long hauls. I have checked all fusing. Wiring seems to be fairly small, and that is an easy change, but not convinced that is the issue. Has 14 gauge running to the back. My question to you all is what have you done to improve the charging? I have 4 golf carts in the trailer. Thanks in advance for your responses.

asked by: Adrian B

Expert Reply:

Great question!

The 12V power supply on your 2003 Chevy Silverado 2500 Duramax will power interior lights and basically provide a trickle charge to your trailer battery bank to keep it from casually dropping but there just isn't enough power to actively charge the batteries - for that you need a battery charger.

I recommend using the 25 Amp Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D because it uses larger gauge wire for the setup and will actually boost up and read what your battery bank needs to actually produce a charge from the alternator on your truck. One of the cool things about this system is you can eventually tie in a solar panel like part # RED45VR to help with the charging!

The BCDC does require some special parts so we've put together a whole kit you can use as the Trailer Installation Kit # e79ZR.

I'm linking the installation instructions as well as an installation video we did for you to reference as well.