In October 2007 — a full 51 months (4.25 years) later, the battery started to loose cranking power. We discovered it had a bad cell, but it continued to work fairly well. In early November, Steve got stuck - the battery wouldn't start the car. Steve went to a nearby Wal-Mart. Normally batteries in Arizona don't last more than 3 years, so Steve was prepared to pay full price to replace our old battery.
The service tech at Walmart offered us free installation of a new EverStart Maxx battery AND because of the pro-rated warranty we only paid $15.93 . . . 15.93 for a new battery!
Now we've had batteries with replacement warranties before, but they've never been this generous! The full retail price was supposed to be $73.48. We received a savings of $57.55. Steve questioned the Automotive Department manager to make sure she was performing the transaction correctly. It just didn't seem right. She checked it twice and then re-explained Wal-Mart's warranty policy. The new battery has a 36 Month Full Replacement / 108 month prorated warranty.
We know that customer service varies from store to store. Just be aware that enforcement of the proper terms of any warranty depends on your knowledge of the terms and the helpfulness of the customer service person. Know the details and stand up for what is right.
Ours is not an isolated experience - read what other Wal-Mart Battery Owners are saying:
2015 update: The Walmart battery warranty is constantly changing, so whenever I get a new battery, I ask for the manager, confirm the warranty policy and write it on the envelope for the warranty (that I keep in the glove compartment).
Bottom line: ask questions, take notes and keep a record. You'll be happy you did!