Automotive batteries ALL have a pro-rated warranty, no exceptions, which equates to end of warranty, it's worth ZIP. I change out all my starting batteries every 4 years. I keep them topped off with distilled water (even the so called maintenance free ones) and I keep the terminals all clean and bright as well as the main grounds to the frame and they all get coated with anti-corrosion treatment, I use Fluid Film clear on them. When my tractors sit a long time (in the winter), I disconnect them from the tractors with a positive disconnect knife switch in the NEGATIVE post, never the POSITIVE as there will always be a litte parasitic drain and flooded cell batteries only have internal drain at about 5% per month when idle and finally, I buy ALL my batteries at a volume dealer, in my case, a heavy truck dealership because they turn over batteries quickly and keep in mind that ANY flooded cell storage battery, ONCE the electrolyte is added, the battery is slowly dying sitting on the shelf waiting for you to buy it and heavy truck batteries are all way over built compared to box store batteries. Built withstand vibration much better. I like Interstates (Johnson Controls) and Alliance (Freightliner) batteries.
