Battery Basics for Care & Maintenance

With all of the electronics in trucks today, the battery plays a significant role in keeping everything up and running. Today’s batteries are much more sophisticated than they used to be, and good care and maintenance are essential.

When replacing a battery, ensure it meets the requirements set by the OEM. The following descriptions indicate requirements for selecting a replacement battery.

Group Size – The group size indicates the battery’s outside dimensions and terminal location of size standards established by the Battery Council International (BCI). Every battery is designated a BCI Group Size number to assist in identifying a correctly-sized replacement.

Cold Cranking Amperage – Cold Cranking Amperage (CCA) rating tells the amount of current (in amperes) the battery can deliver for 30 seconds at -18 degrees C or 0 degrees F. Voltage at the terminals must not drop below 7.2 volts during or after a 30 second discharge period. The CCA requirements are usually higher as the engine displacement increases, depending upon starter current draw requirements.

Ampere-Hours – This rating indicates the current (amperes) the battery can steadily deliver for a 20 hour period with the battery voltage not dropping below 10.5 volts. It may also be identified as the 20-hour discharge rating.

Load Test Amperage – This rating indicates that the current (amperes) battery should be tested by using battery load test equipment.  The rating should always be 50 percent of CCA. For instance, if the CCA for this battery is 600 amperes, Load Test Amperage will be 300 amperes.

The battery is not designed to last a lifetime; however, with proper care, it should provide years of service. If the battery tests well but it fails to perform as expected, some of the common causes may include:

  • The vehicle accessory may have been left on overnight.
  • Slow driving speeds with frequent stops while using many electrical accessories, such as the air conditioning, headlights, wipers, heated rear window, etc.
  • The electrical load has exceeded the generator output due to the addition of aftermarket equipment.
  • Charging system conditions, which may include the alternator belt slipping, the generator not charging or improper battery maintenance, like a loose battery hold down or missing battery insulator.
  • A short, pinched wire or bad ground in the electrical system attributing to a power failure.

Most OEMs have guidelines to follow when disconnecting, replacing, installing or connecting the battery. TruckSeries truck repair information provides articles that cover battery specifications, descriptions and operations, general procedures, removal and installation. It is best practice to always review these items when servicing a battery and follow safety procedures to prevent any injuries.

Also, read:

Tips For Diagnosing Intermittent Electrical Issues

Diagnosing Parasitic Loads


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About the Author

Bruce Cansler

Bruce Cansler started his automotive career in 1973 as a technician for Datsun. He retired from the U.S. Navy as a Seabee Construction Mechanic with 20 active years of service and 10 as a reservist, then spent time working in Ford, Lexus and Caterpillar dealerships. Bruce has obtained ASE certifications in both cars and medium/heavy trucks and has worked with the Commercial Vehicle Group at Mitchell 1 since 2009.