When To Replace Coach Batteries?

CVD wrote:
I had a little corrosion on the walls of my battery tray, so I took them out to inspect. No structural harm, so I scrapped, sanded, painted the tray; now ready to put the batteries back in. At what point does it make sense to replace them as a preventive step?

These are 4 Sam’s Club (Johnson Controls) 6V EGC2 batteries, manufactured Feb 09 (8 + years ago).

They’ve consistently used only a couple spoonfuls of water every 2 – 3 months (per cell).

After sitting in the garage a couple days, each still measured 6.32 to 6.35 volts. (Don't have a shunt&Trimetric type device to measure more accurately).

They’ve worked fine. With light electricity use, I’ve gone 5 – 6 days boondocking without running the generator (have single 140w solar panel).

There was a little corrosion on a couple terminals and in the horizontal seam just below the top cap. Easily cleaned up.

There is a very slight bulge on the two ends of each battery (exact same on all 4). Don’t remember if they were this way when I put them in years ago.

Bottom line – They have been working fine, but I wonder if it makes sense to change the 8 year old batteries at home when I’m ready (instead of on the road when I’d rather be doing other things)?

With our old coach, every house battery change was done so, while on the road. Once in a WA state Sam's parking lot during lunch and another time in a NJ campground. No biggie and even though I'm running 4 AGM 12v now, I'm not about to fix what's not broke, but do hope to take advantage of my 5yr full replacement warranty with these and no matter where I might be.
I mean how can one predict when something will need fixing anyway, as issues can arise out of nowhere. I mean maybe I should have changed my starter out, ahead of time and twice in fact, with our old gas coach, rather than do so in a TX parking lot and in a FL rest area, whaddaya think?