Many owners swear by Interstate batteries. The Interstate Mega-Tron Plus MTP-24 is a standout in tests, delivering exceptionally long life even in searing, battery-killing temperatures.
Shines in tests and real-life use. The Interstate MTP-24 sails through hot-weather stress tests. It's not quite as powerful in freezing weather as the top-rated DieHard Advanced Gold 50778 (Est. $165), and it won't last quite as long if you leave your lights on accidentally, but it's very good in both situations. Other sizes of this battery like the MTP-48 and MTP-35 perform very well, too, but the MTP-75 lags behind in some tests.
Ask around, and you'll probably hear Interstate batteries recommended more than any other. We found more consistently good owner feedback for this brand than any other type of car battery, including a snowplow driver in upstate New York, a semi truck fleet manager and others with power-hungry vehicles.
Extremely durable. This is a lead-acid battery with removable caps, but it's still designed to be maintenance-free so you won't have to top off the water. It carries a shorter warranty than some: 30 months replacement/72 months prorated, versus 36/100 for the DieHard Advanced Gold 50778 and Kirkland Signature 12866 (Est. $85). Still, the Interstate proves exceptionally durable in tests and plenty of owners back that up, from the farmer who got more than seven years out of an Interstate battery in his grain combine to the off-road enthusiast who inherited an Interstate eight years ago in a used truck and it's still going strong.
A mid-priced owner favorite. For about $40 more than the Interstate, you can get the DieHard Advanced Gold 50778. For $40 less, you could get a Kirkland Signature 12866 at Costco, but you'll have to install it yourself. Both prove a bit more powerful than the Interstate car battery in a leading test. Still, for many users, it's Interstate all the way. As one owner in freezing Colorado puts it: "Every Interstate Mega-Tron battery I have owned has lasted me over ten years ... I will not buy any other brand."
The Interstate Mega-Tron Plus MTP-24 is one of 56 car batteries tested here. Editors rank the batteries from best to worst, based on their performance in tests of life expectancy, cold cranking and reserve capacity. Subscribers who own the battery also post feedback.
Review: Interstate Mega-Tron Plus MTP-24, Editors of ConsumerReports.org, April 2013
You can't just go by brand when shopping for car batteries, ConsumerReports.org warns in this free article. Big-name brands -- including Interstate -- top the ratings in some sizes, "but they are at or near the bottom in others."
Review: Beware: The Best and Worst Replacement Car Batteries Can Be From the Same Brand, Jim Travers, April 26, 2013
Six customers review the MTP-24 here, and all but one award it a perfect 5 stars. The lone 1-star review comes from someone who drives only 10 minutes per day; Interstate responds that that distance may not be enough to keep the battery charged, and it may simply need to be recharged.
Review: Mega-Tron Plus 24 Automotive Battery Six-Year Performance 800 CCA, Contributors to InterstateBatteries.com, As of February 2014
On this forum, Toyota Land Cruiser enthusiasts discuss which is the best car battery. Several recommend Interstate batteries, even over pricey Optima batteries.
Review: DieHard Gold Battery or Interstate Mega Tron Plus?, Contributors to IH8Mud.com, December 2013