Your alternator is one of the hardest-working parts of your vehicle. It’s a common misconception that the battery in your vehicle is what supplies your power while the vehicle is running. The alternator not only supplies power to all of your vehicle’s electrical components while the vehicle is running, but it’s also recharging your car battery at the same time.
Every time you use your headlights, radio, GPS, air conditioner, heater, defroster, power seats, turn signal, dome lights, or power outlets, your alternator is making it all work by turning mechanical energy into electrical energy.
Needless to say, when it dies, your car can’t function. That makes its replacement a pretty big priority. To keep you prepared for potential alternator failure (an increasing possibility as a vehicle age), here’s a look at what it costs to replace one of these miniature power plants.
How To Replace an Alternator?
Following are the step of Replace an Alternator
- Disconnect the Battery.
- Disconnect the Wires.
- Remove the Belt from the Pulley.
- Remove Bolts.
- Halfway There.
- Examine the Replacement.
- Reverse the Removal Steps.
Step 1: Disconnect the Battery
First and most importantly: disconnect the battery. There may be several wires or just one wire on your alternator, but rest assured that one of them is hot.
If you don’t disconnect the battery, you’re very likely to end up grounding a live wire during the process. This causes cause all manner of bad things to occur not the least of which is giving you quite a shock.
Step 2: Disconnect the Wires
Now that the battery is out of the way disconnect the wire or wires from the back of the alternator. This is usually a very simple process but if you’re unsure as to where they go, label them as you take them loose.
Step 3: Remove the Belt from the Pulley
Every project has a tough spot, and this is the tough spot for alternator replacement: remove the belt from the pulley. Somewhere in your vehicle, there is a tensioner pulley. You’ll need to move it enough to slip the belt off the pulley. Our ’95 GMC has a standard spring-loaded GM tensioner that required us to pull it back with a wrench.
On some vehicles, you’ll find screw-type or rod-end type tensioners that apply tension by turning a bolt through threads to increase/decrease the length of a rod. In this case, just turn the bolt/rod-end with a wrench or socket until it releases enough tension to allow you to remove the belt.
In our case, we grabbed a Craftsman 17mm Cross Force wrench and pushed hard. Normally that would be a pretty painful experience, but the Cross Force was designed for just such a situation.
There’s a 90-degree twist in the middle of the Cross Force wrenches, so you end up pushing on a flat surface. The result: we could push harder without discomfort. So we just laid into it and the belt came free.
Step 4: Remove Bolts
Once the belt is off just removed whatever bolts connect the alternator to the bracket and you’re good to go. Our model required the removal of three bolts: one at the front and two at the rear.
Step 5: Halfway There
With the old alternator in your hand, you’re halfway home. You’ll likely find getting the new one back in goes much faster since you already know what size the bolt heads are and where everything is.
Step 6: Examine the Replacement
Examine the replacement unit before reassembly and make sure it will work for your application. Our replacement was a junkyard find so it is great to deal dirtier however it has the advantage of actually working a significant improvement over our previous busted unit.
Step 7: Reverse the Removal Steps
To complete the project just reverse the removal steps paying careful attention to belt routing and tensioning. Hell, even if you bought the set of Cross Force wrenches for the job, you’d still be hundreds ahead of the cost of what a shop would charge and you get some new tools out of it. We can think of far worse outcomes.
Alternator Replacement Cost
The average cost for alternator replacement is between $573 and $742. Labor costs are estimated between $123 and $155 while parts are priced between $451 and $587. This range does not include taxes and fees and does not factor in your specific vehicle or unique location. Related repairs may also be needed.
When you start noticing certain issues, it’s time for an alternator replacement. You can go to your local auto shop to get this work done. But you should be prepared for a hefty bill.
- New alternator: $200 – $500
- Labor: $100 – $200
Your prices may vary depending on the make, model, and year of your vehicle. Additionally, you may be able to save even more money by replacing the alternator yourself. But you should only do that if you’re confident in your ability to do vehicle repairs.
Can I still drive with a bad alternator?
While you can technically still drive with a faulty alternator, it’s ill-advised. The alternator charges the battery. So, when it starts to go bad, the battery drains more quickly. In addition to needing a new alternator, you may also need to pay for a new battery on top of it.
Do You Have to Replace the Battery When Replacing the Alternator?
Your alternator is run by your serpentine belt. On nearly all late-model vehicles a serpentine belt, or drive belt, is used to drive the main pulleys, and this must be removed in order to remove the alternator.
If the belt hasn’t been replaced in some time or is showing signs of cracking or wear, now is the perfect time to replace it. It will already be part of the labor to remove the alternator, so the only added cost is the price of the belt.
In rare instances, the wiring harness plug that plugs into your alternator is also replaced. This is only the case when excessive heat has caused the plastic plug to deteriorate or even melt. The last item which may require replacement, along with your alternator, is your battery.
Starting your vehicle takes pulls a lot of energy from your battery. If the alternator wasn’t recharging it constantly, it would only last for a couple of starts. If your alternator fails, your vehicle will still need the power to operate.
It will find this power in your battery. Unfortunately, without your alternator working to recharge it, this could do some damage to your battery’s cells. Sometimes you get lucky and the battery survives the strain. The technician usually finds that out with a quick test before the work even begins.
You don’t have much time when the battery is on its reserve, a 12v battery typically runs for roughly 30 minutes to an hour after the alternator has stopped working. In this case, it’s best to immediately drive to the nearest auto shop to have your alternator replaced.
Will insurance cover an alternator replacement?
Alternators usually die from normal wear and tear. As a result, insurance policies typically don’t cover the cost of a new one. The only exception would be if the alternator was damaged in a car crash.
Your insurance policy can still help you out immensely. When you have a policy that comes with roadside assistance, you can get towed to the nearest shop. This comes in handy if a bad alternator leaves you stranded on the side of the road. You never know when a bad alternator may strike, so having an insurance policy that you can depend on is key!
The alternator is a critical part of your vehicle that serves many important functions. Understanding the warning signs of a failing alternator and how much you can expect to pay for a new one can prepare you for when you need to replace the alternator on your vehicle.
(These repair prices can also fluctuate based on geographic location, as well as vehicle make and model; these numbers represent averages, not actual prices offered at any specific auto repair shop.)