What is one of the first things you will need to consider when purchasing a second-hand car? If you thought of checking the odometer reading you would be very right.

What does the odometer do? The odometer is a recording device that is built into a speedometer to show the distance a vehicle has travelled. The speedometer and odometer are driven by a cable which is housed in a casing. The cable is connected to a gear at the transmission. This gear is designed to match a specific car model, tyre size and rear axle ratio. When a vehicle is moving, a set number of revolutions of the drive cable measures the kilometre/mile travelled.

The odometer display can either be digital in its display, or the numbers recording the mileage can be painted onto the set of turning cogs which flick over in a set pattern as the distance is travelled. These cogs are part of a gear train system that is connected to the speedometer.

Most odometers record the total distance travelled. Some odometers also record the distance of individual trips. These individual trips can be reset to zero.

The analogue speedometer used on cars indicates the speed of the car and records the distance travelled. Speedometers will be calibrated in either miles per hour and/or in kilometres per hour depending on which country of use the motor vehicle is designed for. Speedometers need to be inspected and lubricated to prevent the cables from breaking.

Unscrupulous car dealers have been known to wind the odometer back. However, they can be caught out, because often the amount of wear and tear on a car gives a buyer a clue that the car has done more kms than the odometer suggests. Example of this tell-tale wear include the clutch pedal and the fabric on the driver’s seat, among others. If the clutch pedal looks a bit too worn for the low kms on the odometer – or is suspiciously new compared to the other pedals, get suspicious.

The odometer is colloquially referred to as “the clock”.

We hope that helps answer the question ‘What is What is an Odometer?’!

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