What is Odometer Service? (Explained)

One of the most important things you need to know about your odometer is that it should always be calibrated according to the right specifications.

That’s because every odometer is calibrated based on the size of the tires.

So, in that sense, you may have heard of something such as odometer servicing in relation to your odometer’s calibration.

What exactly is an odometer service and what is it for?

Odometer servicing is a service that is aimed at correcting or re-calibrating an odometer that may be working normally but is not calibrated properly. This is usually necessary whenever you changed the size of your tires and you were not able to properly calibrate the odometer based on the new tires.

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When it comes to your odometer, you need to understand that there are plenty of things that are tied to how it should be calibrated properly.

That’s because your odometer is what determines your mileage, which is very important when it comes to selling the vehicle in the future.

As such, it is important that you have your odometer go through service if you believe that it isn’t calibrated properly.

What is odometer service?

When it comes to the many instruments that you see on your car’s dashboard or instrument cluster, one of the most important instruments is the odometer.

While you don’t always use your odometer as you don’t look at it on a daily basis while you are driving your car, it is important to note that the odometer is vital because of how it is a federal offense to tamper with.

You may even run into some legal issues if your odometer does not accurately reflect your car’s mileage.

That said, there are many different types of services that vehicles go through but one of the services you probably haven’t heard of or you have not hard as often as the others are odometer servicing.

After all, not everyone actually has their odometer go through servicing.

But what exactly is odometer service?

Simply put, odometer service is the type of service that your odometer receives if there are any issues with it. That means that your odometer might not be working well or it might not be functioning the way it should.

In most cases, this happens when your odometer is showing an inaccurate reading even if the odometer itself might be functioning normally.

In short, odometer services are there to fix your odometer’s inaccuracy by re-calibrating the odometer according to your car’s correct specifications.

This usually happens when the odometer is inaccurate or is not properly reflecting the vehicle’s correct mileage.

Read more on odometer correction.

Why would your odometer need servicing?

Now that you know what odometer servicing is, you might be wondering why your odometer actually needs odometer servicing in the first place.

Well, for starters and as mentioned, odometers go through servicing if there is a need to fix, correct, or re-calibrate the odometer according to what they are supposed to do or to the vehicle’s proper specifications.

In most cases, your odometer needs servicing because it isn’t showing the right mileage or due to how it is not calibrated according to the right specifications.

While this is something that you can probably do at home if you have a car with an older mechanical odometer, this isn’t usually something that you could do on your own if you have an electronic or digital odometer, which has become the standard in most vehicles today.

Still, if you do have an older car, there is a chance that you could service the odometer yourself especially if the odometer is mechanical.

All you need to do is to open up your car’s dashboard using screws and then unscrew the odometer from it. 

You will be able to see certain gears behind the odometer, and what you can do there is to replace one of the gears that are connected to the output shaft, which is connected to your vehicle’s transmission.

Replace the old gear with a new one that is actually made specifically for the size of your vehicle’s tires.

Read more on how odometers break and how to fix them.

Why is an odometer not calibrated accurately?

Now that you know what odometer servicing is and why you might want to have your car’s odometer serviced, the one thing that you may be wondering now is why in the world is your odometer not even calibrated properly.

In that regard, what you need to know is that an odometer is calibrated based on the size of your car’s tires.

That’s because the odometer uses an equation that calculates the miles that your car has traveled based on how many revolutions the tires have made and on how big the tires are.

So, in that regard, the equation uses the tire size as a constant in determining the vehicle’s correct mileage.

When you buy a car, its odometer has already been calibrated based on the size of its stock tires.

But there will be times when some car owners replace their stock tires with newer ones that are bigger than the older ones. 

Naturally, bigger tires are capable of covering more ground.

So, if you are using bigger tires but your odometer is still using the old calibration with the smaller tires, the odometer will show a mileage that is actually lower than the miles that your vehicle has traveled.

As such, this can be tantamount to fraud on your part because you did not do your part in allowing your odometer to reflect its actual mileage.

As such, when you replace your old tires with newer ones of a different size, you should also have your odometer serviced and calibrated to the specifications of the new tires.

This will allow you to have an odometer that actually reflects your vehicle’s correct mileage.

If you are using a second-hand car and you have a reason to believe that your odometer is not calibrated properly, what you can do is to drive one mile on the road using road markers.

After that, try to see if your car’s odometer was able to properly reflect the mile that you drove. If not, then it could be due to how it was not calibrated properly.

As such, it is important for you to have it re-calibrated as soon as possible by having your odometer go through servicing.


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