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Choosing a Battery

Causes of Battery Failure

Heat: Heat is a major factor in battery failure. If your vehicle is equipped with a battery heat shield, make sure it is installed properly. The battery heat shield is usually made of plastic and fits snugly over the battery.

Vibration: Vibration causes the breakdown of the internal parts of the battery. Minimize the effects of vibration to your battery by assuring your battery fits properly. Also make sure the battery hold-down is installed correctly and holds the battery firmly in place.

Malfunction of the charging system: A malfunctioning charging system, either overcharging or undercharging, can shorten battery life. Your charging system should be checked yearly to make sure it is operating at peak performance.

Corroded cables: Keep cables clean. (See “Battery Maintenance” for more information.)

Low electrolyte: Maintain the proper fluid level in your battery. (See “Battery Maintenance” for more information.)

Purchasing a New Battery

Eventually, every car will need a new battery. The “one-size-fits-all” batteries found at large retail stores may be more of an expense and headache than they are worth. Battery ratings, physical size, and post location are important factors in ensuring the proper fit and function of your battery. In fact, choosing the wrong battery can adversely affect the entire electrical system of your vehicle.

Quick Tips

Select a battery of the same physical size as the original equipment battery. This will ensure proper fit of the battery hold-down and avoid any clearance issues.

If your vehicle is equipped with a protective cover over the battery, be sure it will fit the replacement battery. (This cover is usually made of plastic.)

Never install a battery with a rating lower than what the manufacturer recommends. A higher-rated battery will work effectively if it fits properly, but a lower-rated battery will have an adverse affect on the vehicle’s electrical system.

Purchase from a large volume seller. Getting a fresh battery is important. Most batteries have a life span of three to five years. Don’t buy a battery that has been on the shelf for months. The life span includes the time the battery sits on the shelf.

Date Codes: The Key to Getting a Fresh Battery

Most battery manufacturers record the date the battery was manufactured or shipped from the factory (the date code location on the battery can vary by manufacturer). Date codes can be found either stamped in the top edge of the battery case or on a sticker affixed to the battery. Letters commonly identify the month: A for January, B for February, and so forth. (Some shipping codes do not use the letter “I,” as it may be confused with the number “1.” In these cases, J would reflect September, K for October, L for November, and M for December.) The number (following the letter) identifies the year. Therefore, the date code “B9” signifies a battery freshness date as February 1999. This code sequence is used by GNB, Interstate, and other popular battery brands.