How Long Alternators Last

First, let’s cover what an alternator does & how it works - an alternator is supposed to change mechanical energy into electrical energy. You can get it from different Wrecking Yard Parts in any Junk Yard.

Easy enough, right?

Just think, before all of that fancy stuff came out, all alternators had to do was power the headlights on your car. Now, it has to power different things like your radio, your GPS system, the heaters that come in the seat, and even your DVD players. If your alternator is failing, then it’s obviously time for a new one.

Hopefully we all know that nothing lasts forever - well Used Auto Parts don’t last forever. Since it powers so many things and since there’s so many factors that affect its life, you can’t really pin point an exact time when it’s going to give up on you; I guess you just have to prepare yourself for when that time comes. It all really depends on the type of car you have, the type of engine that’s installed, the different conditions you drive it in, how much electrical stuff you have in it, and different things like that. There are some cars that will lose their alternator’s life at 40,000 miles and then there are cars that have an alternator that will last 100,000 miles.

When your alternator is starting to wear out, you’ll notice that you’re going to lose some power in some of your electrical components from your car - this will usually happen when your car is idle. The reason why this happens is because you have nothing to recharge the battery. If this happens, you can probably get a quick jump-start from either a friend or a really nice passerby .. but just know that the car isn’t going to last that long with an alternator that’s dying.

Since I know you don’t want to be stuck stranded in the middle of the road, here are some preventative measures that you can take so that doesn’t happen.

When you test the health of your alternator, you’re going to want to use a voltmeter; it’s a special gadget that measures the electrical output. Before you use it, you need to start your car, make sure that all of the added accessories are turned off, and then you have to get the engine to a state of a healthy idle. After this, you’re going to want to pick the “DC” scale on the voltmeter, connect it to the battery terminals, and then look at the reading that pops up on the device. The number that should pop up is either 14 or something around there.

After this, you should start turning on the accessories like the headlights, radio, heater, etc. - if the number at anytime drops below 12 volts, then your alternator really isn’t doing what it’s supposed to. You need to make sure that it’s the same voltage that’s coming from the alternator terminal. If it’s not, then the battery may be the problem - not the alternator.

If you really want to, you can even replace the terminal clamps. They can eventually weaken to the point where they can’t provide contact anymore .. which will lead you to the wrong reading.

At the end of everything, and you realize that your battery isn’t the problem, you may just want to replace your alternator. All you really need to do is get a used one from a place with Wrecking Yard Parts and you should be just fine.