So, how long can house batteries last?

If it's of interest to you.

Step by step instructions for testing deep cycle batteries

Mine lasted 7 years, but for at least half of that time, I abused them with a single stage charger, and less than frequent water checks. When I finally did get around to checking the water, the pair of group 27 batteries never took less than 3/4 of a gallon, between them. I am really surprised that thay lasted that long.

I upgraded to a 3 stage charger after 4 years. I finally replaced my batteries a couple of months ago with a pair of 6v golf cart batteries. I am vowing to check the water more frequently.

On normal flooded golf cart batteries, I figure 30~36 months
But we full-time off grid, mostly dry camping
Do that is around 1000 use cycles, charging..discharging

I'm currently running a couple T105s that are approaching 12 years old and still work well. They were 8 years old when I acquired them. I don't think they were ever really used before I got them, and I haven't strained them much either. They've spent most of their time in maintenance mode. I'm considering replacing them this year just because.

If you *never* boondock, and it doesn't sound like you do, you only need one 12v battery. I guess you could let those die of old age.

A much bigger shock will be if they die on a camping trip and you're nowhere near a store.

I got 7 years 11 months out of 2 OEM T-105's
Then got 7 years 3 months out of the replacement 2 T-105's

Just put a PowerPulse on the 1 year 5 month old replacement T-105's.
Will know in another 6 years if it helps or not.

8 yrs no problem for 6 volts, been there.

Not sure about 12'ers, but mine at near 5 yrs now, and looking good.

My secret, a PD wizard conv/charger. Whatever they do, they do it right.

You state "never discharged" them :h
What is your meaning by this? Do you not use them? Or are you saying you never let them get below a certain voltage?
The number of draw down cycles will greatly effect the life of a battery.

One to ten years or even more. Depends mostly on how they are cared for.

I figure minimum seven years for my use.

Your 2006 batteries must be nearing the end.

The last time I purchased a marine battery for my camper was about 4 years ago. I bought it from Batteries Plus. The warranty, or guarantee on any of them was only 1 year. For over $100 a battery, I was REALLY disappointed. We sold that camper about 2 years after that. When we sold, the battery was still doing very well. The original battery that came with the camper lasted 6 years.

So you know .... is anyone's guess these days!