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Some alternators are easily accessible and can be serviced from under the hood of your vehicle. Others are located near the bottom of the engine and may require raising the vehicle be on a lift to access the alternator for replacement. In some cases, removal of other components such as the tire and wheel assembly, splash guards, drive axle, engine mounts, or A/C compressor may be required to replace the alternator, which increases the level of difficulty.

How Difficult is Installation of Alternators


What is an Alternator?

An alternator creates a current by spinning a magnet around at high speed, then running the current through a current rectifier. A rectifier changes alternating current (AC) into direct current (DC), enabling the alternator to produce power to run all of the electronics in the vehicle and charge the battery.

How do Alternators Work?

Your vehicle’s alternator is part of its starting and charging system. Its primary job is to maintain the charge of your car battery. Alternators produce AC power through electromagnetism which is formed by the stator and rotor relationship. Alternators convert AC current into DC current to power the vehicle’s electrical system and maintain the battery’s correct state of charge

How are Alternators Made?

Alternators found in most passenger cars and light trucks are relatively small and lightweight. Most are constructed using an aluminum outer housing, as the lightweight metal does not magnetize and can dissipate the tremendous heat generated from producing the electrical power.

Why do Alternators Fail?

  • Alternators have various moving parts that are subject to stress from heat, cold weather, and moisture. As a result, the internal parts gradually wear out.
  • Alternators are subject to contamination from chemicals and the surrounding environment like oil, dirt, salt, etc.

What are Symptoms of Alternator Failure?

  • Dim lights
  • Drivability or engine performance issues
  • Warning lights staying lit
  • Weak or discharged battery
  • Burnt smell from the alternator
  • Unusual noise or loud grinding sound coming from the alternator
  • Malfunctioning of various electrical systems

These symptoms do not necessarily indicate a failed alternator; further testing is always required.

What are Consequences of Alternator Failure?

  • Battery drain
  • Battery damaged
  • Engine stalling/drivability issues
  • Electrical charging system failure.
  • Starter motor failure.

If you have questions or concerns about alternators or any of your vehicle’s components, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need. If you want to learn more about other car parts, especially as they apply to alternators, we recommend reading up on car batteries, starters, and catalytic converters.