Whichever brand you find, you want an AGM battery with external venting and reversed posts. Optima battery and installation kit for Prius 2001 to 2003 is one. Ideally it would have JIS posts, this battery does not, it includes a kit to convert to SAE posts.
It's important to know which battery you've got in the car now. If it has never, ever been changed before in the life of the car, it will say GS on the side and have the smaller, JIS posts. If a dealer ever replaced it after October 2003, it says Panasonic on the side and has larger posts: the tray, holddown, and terminal clamps will have been changed at that time. If that was never done, you can get the Toyota-designed tray, holddown, and terminal refit kit for about $33 (part number 04003-23147). That will put your car in the official stock condition to fit your choice of the current Toyota battery or any other battery with its larger size and posts. (As an aside, mlibanio in another thread found the specs of the current Toyota battery, the Panasonic, and it compares quite favorably to other batteries people are using.) -Chap
The dealer stuck some sort of interstate battery in the 2002 as the original (?) GS was done for. I need to convince them to either replace it with a Toyota or elearnid Optima kit OR take off $200 bucks from the price and I will give them wrong battery back and put in the Optima Kit.
Are you certain its and Interstate battery? Most dealers would only use the stock battery. If they did put it in and it works fine, why change it?
