I replaced mine after 7 years, 83,000 miles. It still worked fine, but was leaking a bit around one of the terminals. Canadian 4Runners (at least mine) don't come with a Panasonic battery. They come with a Toyota battery generally better suited to our climate (850 CCA, 140 min RC). I replaced mine with an Interstate, which has the same specs as the Panasonic (710 CCA, 165 min RC). Since I live in an unusually warm part of Canada that doesn't get below freezing I opted for more reserve capaticy over cold cranking amps.