The Chevrolet Silverado was introduced in 1998 and replaced the Chevrolet C/K series nameplate. The 2003 Chevrolet Silverado featured a 4.3-liter V-6 engine in the base model. Among the 1500, 2500 and 3500 series trucks, the 2003 Silverado featured 11 sub-models. The battery on the 2003 Silverado 1500 is located directly behind the driver's headlight and radiator core support. Replacing the battery requires no prior mechanical experience and can be accomplished in less than an hour.
Open the hood of the Silverado. Remove the battery cables from the battery, using an 8 mm open-end wrench. Tuck the battery cables to the side of the battery.
Remove the battery tie-down bolt, using a 3/8-inch drive ratchet and socket with a 6-inch or longer extension. Turn the bolt counterclockwise to remove it from the battery cradle. Remove the tie-down bolt and the small triangular tie-down wedge from the battery cradle.
Lift the battery from the engine compartment using a battery puller or your hands. Set the battery away from your work area.
Install the new battery into the battery cradle. Install the battery tie-down wedge and bolt. Tighten the battery tie-down bolt between 140 and 180 inch-pounds. Use a 3/8-inch drive torque wrench, socket and extension.
Install the black battery cable to the negative (-) side of the battery, and tighten it to 108 inch-pounds of torque, using the torque wrench and an 8 mm socket. Install the red cable onto the positive (+) side of the battery, and tighten it to the same torque.
Turn on an ohmmeter to the "V" or volts setting. Place the red probe from the ohmmeter onto the positive (+) battery terminal, and place the black probe onto the negative (-) terminal. The battery terminals are located at the end of the battery cables, where they are connected to the battery.
Read the ohmmeter to ensure you have between 12.50 and 12.75 volts output from the battery. If the battery is lower than 12.00 volts, take the battery back to the place of purchase and ask them to charge the battery or supply you with a different battery that is already charged. The aforementioned voltage is the common battery charge for a battery when the engine is off.
Turn the engine of the Silverado on. Attach the probes to the battery again and read the ohmmeter. If your ohmmeter provides a reading between 13.5 and 15.0 volts, then the alternator is charging the battery. If the ohmmeter provides a reading less than the ones given, or no reading at all, then the charging system is malfunctioning.
Turn the ohmmeter selector gauge to the amps setting, notated by an "A" on your ohmmeter dial. The settings within the "A" dial range are marked with a lower case "m" after each number. Set the dial to 200m. Attach the probes to the battery and read the ohmmeter. The reading should be no less than 105 amps and no more than 145 amps. If the amperage reading is not within these specifications, then the alternator should be replaced.
