Free: Contests & Raffles.
2 trojan 6 volts. True deep cycle
I am replacing a diehard silver that was purchased in 2011. All toy batteries are kept on battery tenders Not sure why this one died but it's getting an error message and says replace battery It will not take a charge fluid levels are all good Les Schwab what's 129, Costco wants $79, both are comparable batteries. I just can't see the batteries would have that much difference 50 bucks wise.
We used to have a system that I maintained that had well over 12 Trojan 6v batteries at any given time to maintain. If cared for the Trojans are hard to beat, but most systems are not optimized with them and cannot sufficiently charge them to keep the plates clean and at their best. Battery tenders are good but batteries should be equalized regularly for best life. 4 years for a battery in your RV seems like a pretty good stretch, I wouldn't expect much more than that depending on your use. Hopefully your new battery will be isolated or stand alone from the older batteries, adding a new battery to an old bank is a great way to shorten the life of the new one.
Do some research, you may be really surprised how few actual battery manufacturers there really are and how many different labels get slapped on batteries that roll off the same assembly line.