Where to get speedometer calibrated

Speedometer calibration uses electronic signals to measure the actual output of the speedometer and compare it to the established output standard that is set by the manufacturer of the vehicle.

If a difference between the instrument reading and the accepted standard is determined and verified, the calibration device can tune the speedometer in order to provide the correct speed measurement. This process makes the speedometer readings more exact and, as a result, the odometer reading more exact as well. The accuracy of speedometers is important because it ensures users they are driving within legal limits and avoiding expensive moving violations and high insurance costs, as well as other safety hazards.

Read Reviews. As with most electronic instruments, speedometers should be calibrated regularly to ensure proper performance. In order to ensure that the torque created by the magnetic field reflects the speed of the car accurately it must be calibrated.

Calibration services must take a number of factors into account concerning the machine being calibrated, such as gear rations in the drive cable, final drive ratio in the differential and the diameter of the tires.

As a speedometer becomes older, more frequent calibration may be required. Aftermarket modifications to the vehicle, such as new wheels with a different size diameter, low tire pressure, extra weight in the vehicle and environmental conditions can also result in erroneous readings on the speedometer and odometer. Look for the vehicle's axle ratio in the supporting documents that came with your vehicle. It may also be found inside the vehicle's glove box. Divide the solution by 1, The resulting number is the number of driven gear teeth needed.

Contact the vehicle's manufacturer or a local speedometer service location and purchase the necessary driven gear for your vehicle. You must provide the make, model and year of your vehicle to ensure you receive the right gear. Remove the old driven gear from the end of the speedometer cable by pulling it out of the clips that hold it in place.

Clip the new driven gear into place on the speedometer cable. Replace the gear housing cover and secure it in place with the bolt you removed in Step 1. Count the number of teeth the gears have and remember it for later. Purchase the necessary driven gear for your vehicle. Remove the old driven gear by pulling it out of its clips and clip in the new driven gear. Secure the gear housing cover and the speedometer cable back. If you have an electric speedometer, you would start by determining the distance of the test drive you would need to recalibrate your speedometer, which can be found in the vehicles supporting documents.

The variance percentage is also specified. For vehicles registered before , the variance of seven per cent from the real value is permissible. If the registration is after , the speed may exceed the real value by ten per cent plus one extra increase of four kilometres per hour. By buying these tyres, you more than likely have changed the tyre size which can have countless advantages for the handling performance of your vehicle.

If this is the case, you should also have the speedometer calibrated accordingly. Simply stated: If you do not perform a speedometer calibration , the kilometeres will not be displayed correctly and the actual driven speed is no longer accurate. The resulting consequences can be drastic.