I have lived in OH, TX,and TN. Most of my car batteries have failed in the hottest part of the summer - various brands. I do not know why, but I think someone on this site offered an explanation a few years ago. Anyway, I am glad they have failed in warm weather and not in the middle of the winter. Typically. my 'failure' is that it will not hold a charge, or 1 cell died, according to the folks that perform the failure diagnosis. Note that most of my driving is short, in-town driving. My charging systems are A-OK.
IMO, your South TX environment is stressful in itself...
I think that Sears should definitely support you.
I buy 'standard' brands from various popular auto stores, and I have reluctantly come to accept that any car battery lasting >3 years is reasonable, thought I have had some last >6 years (a Camry). As I understand it, there are only a few manufacturers of batteries, and the auto stores buy from various suppliers, so this year's great brand is not necessarily next year's sure-thing. I do believe that within each manufacturer there are distinct grades of battery quality (incl mechanical robustness) and service. Consumer Reports provides some guidance that I have found useful.
2 things I have read and believe - First, newer cars start-up pretty fast, so the strain on the battery is less, overall. Second, to save fuel, some cars turn-off the alternator field if the battery is fully charged, then turn it back on when the battery sags. I had an old Civic that did this, and there was a TSB to reprogram it due to too-aggressive 'off' time. And you know the Civic battery is very small to begin with - that car required more batteries than typical..
In recent years, I have purchased the top Walmart "Maxx" battery with good service success and also good warranty service. They always have fresh ones there, which I think is important, and I measure the open-circuit voltage to be sure. Due to battery chemistry, ideal open-circuit voltage 12.76V, indicating full charge.
Due to my typical short, in-town driving, when I install a new battery I drive it on the highway for about 30 minutes to ensure it gets a good initial charge. I admit this might not make any difference, but it is the best I can do for it.
I wonder if my car that is parked on a sideways slope hurts the battery due to potential for cells not being covered completely - nothing I can do about that, but something to mention if you have options of where to park...
