Car Tire Size / Car battery size / Group 78
Group 78 battery size
A group 78 car battery is at most 10.24 inches long, 7.09 wide and 7.32 tall (260 x 180 x 186 mm), with side terminals (threaded studs on the front).
- Length
- 10.24 in (260 mm)
- Width
- 7.09 in (180 mm)
- Height
- 7.32 in (186 mm)
- Terminals
- side terminals
Close in size
Groups within 10 mm (0.4 in) on every side:
- Group 58: 10.04 x 7.20 x 6.97 in, top posts instead of side terminals.
- Group 58R: 10.04 x 7.20 x 6.97 in, top posts instead of side terminals.
- Group 97R: 9.92 x 6.89 x 7.48 in, top posts instead of side terminals.
Before you buy a group 78 battery
- Read the group number on the label of the battery in your car, or in the owner's manual: it should say 78.
- A group with an "R" after the number has its terminals reversed: do not swap one for the other without checking where your cables reach.
- Choose cold cranking amps (CCA) at least as high as the original, especially for cold winters.
- Group 78 has side terminals (threaded studs on the front): the new battery must match, and the hold-down must fit the box.
- Most stores take the old battery back for recycling, often against a core charge.
Group 78 batteries listed on eBay
Dimensions are the BCI maximums for the case, terminals excluded. Sources: Battery Council International, "BCI Group Numbers, Dimensional Specifications and Ratings" (batterycouncil.org), read October 15, 2026; Power Tool Insider, "Car Battery Group Size Chart" (powertoolsinsider.com), updated October 7, 2026.