Battey Questions

The second battery place on the GMC is for a diesel engine.

If you usually camp with full hook-ups, your need for a second battery is non existant, one will be fine.

Need more info on your camping style

I hate when people do this, but there is a current discussion on this very subject located here:

2nd Battery

My only piece of advice is going with an AGM (no maintenance) battery

WoodGlue

brownieab wrote:
The second battery place on the GMC is for a diesel engine.

If you usually camp with full hook-ups, your need for a second battery is non existant, one will be fine.

Need more info on your camping style

Are you planning on camping places you won't have electric hookups?
For how many days?
What electronics do you plan on running?
Cold westher camping?

ALl these questions play into if a second battery is needed or a waste of money for you.

brownieab fairly well nailed it. MOST people don't need a second battery but if you boondock with no hook ups, it is very helpful to have the extra power.
#1 - Yes you would gain some power from adding a second 12 volt battery but you'd still be using basically starting batteries so they're not going to last very long if you deep discharge them frequently.
#2. Two true deep cycle 6 volt batteries are the MOST powerful option you can use and will out last just about ALL other kinds of batteries. I get over 8 years from a set of 6 volt golf cart batteries.
#3 - Starting batteries are designed to start engines, be they boats (as with marint/RV batteries) or trucks (as in your case. Use a starting battery to assist your diesel in starting. If you have a gas engine you don't need two.
#4. I get 8 years from a REASONABLY well cared for Trojan T 105. They are expensive but WELL worth the money. Lower cost 6 volt batteries may give you the same power but generally don't last as long due to cardboard spacers inside the batteries as opposed to plastic used by Trojan. It's these spacers that prevent warpage of the solid lead plates when batteries are deeply discharged.
#5. Yes there is. You didn't mention cost of batteries (I payed $155.00 each for T 105 from Trojan, two years ago) or anything about how to "turn them off" when not in use (simplest way is to simply remove the negative lead to the RV from it's battery post using a thumb screw) :)
Good luck / Skip

I have switched over to two 6V batterys and love them...alot longer run time.

We normally do 2 - 3 trips a year to campgrounds that do not have hook-ups. For us it was worth it to go to a pair of 6V batteries. We also changed all our interior lights to LED's and on our last 3 day trip the batteries were still reading 2/3 on the panel.

I don't feel the need for the AGM batteries though. Check the levels maybe 3 times a year and you are good to go. Do not let the water level get below the top of the plates in the batteries. Refill with distilled water. If you need to fill more often than this then chances are your charger is cooking the batteries

MontanaCamper wrote:
I have switched over to two 6V batterys and love them...alot longer run time.

X2.. Love the two 6Volts we put on our TT. Last longer. We rarely have hookups, but have been known to top them off with the generator about every 4 or 5 days.

As for our camping style I'll have to get back to you on that we are newbies to rving. It sounds to me like l will replace the deep cycle we have with another to start with. Does anyone have a brand preference? The TT came with an Interstate battery but I have do not have any idea how old it is.

Johnson controls makes the interstates. I believe they also make the batteries for Costco and Sam's. Trojan are usually considered one of the best, but they come at a very healthy price tag. I personally would suggest you go with the 2 6 volts. This will kind of future proof a little. As you start camping more and more you may find that dry camping suits you. at around 85.00 to 120.00 dollar investment it is not to bad. When looking at the batteries look at the 20 ahr rating. for instance interstate makes two one is a 218 ahr and the other is 232. and the batteries are about 25.00 difference. IMHO the 25.00 is well worth the money. Good luck and happy camping.