What Battery Group Sizes to Carry on a Roadside Service Truck

A battery group size is the industry's code for the physical shape of the battery: its length, width, height, and where the terminals sit. Get the group right and the battery drops into the tray and the cables reach. Get it wrong and the driver is standing at the customer's car with a battery that does not fit.

Because there are dozens of groups, most roadside operators either carry nothing and jump everything, or try to carry too much. There is a middle path.

The groups that cover most cars

For passenger cars and light trucks in the United States, a short list does most of the work:

Group	Typical fit	Notes
24F	Many Toyota, Honda, Nissan, Lexus, Acura models	Reverse-terminal version of Group 24; the F matters
35	Honda, Toyota, Subaru, Nissan, Mazda	The most common import size
48 (H6)	Many European and newer domestic cars, GM, Ford, Chrysler	Often AGM in newer vehicles
65	Ford and Lincoln trucks, SUVs and larger cars	Top post, high CCA
75 / 78	GM cars and trucks, side post	78 is the larger side-post size
94R (H7)	European cars, some GM, Chrysler	AGM common
31	Medium-duty trucks, commercial vans, some heavy equipment	Stud or post terminals; needed for commercial calls

Ten to fifteen SKUs across these groups, with flooded and AGM versions where the vehicle mix calls for it, cover 85 to 90 percent of the calls a typical operator runs.

Match the list to your territory

Where you work changes the mix:

• Urban and import-heavy areas skew to Group 35, 24F and 48.
• Rural and truck-heavy areas skew to Group 65, 75 and 24F.
• Commercial and fleet work needs Group 31 on the truck, and sometimes 4D or 8D by order.
• Newer vehicles with start-stop want AGM in the matching group. Putting a flooded battery in a car designed for AGM shortens its life and can trip warning lights.

The easiest way to set the list is to look at your last hundred battery calls. If dispatch has been recording year, make and model, run each through a battery lookup and count the groups. The top eight are your stock list.

How many of each

A one- or two-truck operation usually carries two of each of its top three or four groups and one of the others, roughly ten to fifteen batteries per truck, a $3,000 to $5,000 investment. Bigger fleets keep the same mix per truck and a small reserve at the yard. Rotate stock: a battery that sits on a truck for a year in summer heat loses capacity, so sell the oldest first and top up as you go.

The sizes you do not carry

Everything outside the short list is a pickup. This is the part that used to make battery sales impractical and no longer does: with a partner account and 1,300+ pickup locations, the driver routes past a counter on the way to the call, calls ahead with the group size, and picks it up at will-call. The lookup tool gives the size before the truck leaves the yard.

Checklist for the truck

• The top groups for your territory, two deep on the big three
• At least one AGM in Group 48 or 94R if you see newer cars
• A Group 31 if you take commercial calls
• A load tester and a terminal cleaning kit
• The lookup bookmarked on the dispatcher's screen and the driver's phone

Stock the truck once, pick up the rest en route, and the dead-battery call stops being a jump and starts being a sale. The partner program covers pricing and pickup; the pricing guide covers what to charge.