Using the truck charging system is a doable thing but it isnt CHEAP. Go look at what the rescue squad and police emergency vehicles do to keep all of their radios and emergency gear working...
Back in the JEEP TRAIL days we got along just fine with the inexpensive diode based battery isolators for having two or more batteries connected to the alternator system. With todays smart-mode technology where having more exact required voltages needed to charge the deep cycle batteries the loss of voltage over the old diode based isolators is a killer. My deep cycle battery wants to see 14.4VDC at 20AMPs to start a charge sequence and half way thru this charge mode process it drops back to 13.6VDC. If I was using a diode based isolator which has a high current .7 VDC voltage drop then those DC charging voltages become 13.7VDC for the intended 14.4VDC and 12.9VDC for the 13.6VDC required. The deep cycle battery charging science does NOT work well at those voltages if you want to recharge your batteries in a three hour time frame..
This make you have to install what are called high current SMART RELAYS/SOLENOIDs which are not cheap. The Blue Sea model SI-Series 7650/7610 smart relay cost around $150
This is a planned method for me to charge up a couple of 110AH-150AH Trojan batteries in the back of my truck. I doubt if my 2010 Ford OEM Alternator is big enough to support even this low of current system I am looking at.
Bottom line is high dollar high capacity alternators are required along with high dollar switching components to make it all work...
Nothing is CHEAP anymore...
I suggest you run by what you are wanting to do with MEXICOWANDERER... He lives and breathes this stuff big time...
just my thought
Roy Ken
