I'll agree with the testing of the batteries before you make a disision to buy new ones. a load test isn't jusrt a pass or fail, it shows you if there good, then has a range for week and a fail. so you can see when they are starting to not provide full cranking amps, which may be fine in the summer but for winter it may not be. I bought my own tester just so I could check batterys on my vehicles, and the wife and kids vehicles. a little pricy for the one I bought but it was worth it. it has helped me diagnose a whole bunch of things on vehicles that I thought were the battery and turned out to be something else.
Steve