Larger trucks or performance cars could use a larger group 65 or 78 battery, but be sure to check your battery's label before you go shopping for a new one.

We've tested and reviewed products since 1936. Read CR's review of the Interstate MT7-65 car battery to find out if it's worth it.

It's available in battery group sizes 34, 65, and 78. The technology that gives the MT7 all the “better battery” qualities is called AGM, or absorbed glass mat.

We've tested and reviewed products since 1936. Read CR's review of the EverStart Maxx-65S (South) car battery to find out if it's worth it.

The battery group then corresponds to the size of the battery being tested, ... The largest batteries Consumer Reports tested are in the Size 65 category, for large Ford and Mercury cars, ...

Optima's newest battery is the Group 31, a larger and more potent version of the tried-and-true spiral "6-pack" technology! Check it out inside Four Wheeler Magazine.