Firstly remember: Discrepancy could be a 600 KM difference on 60000 KM or 6000 KM total mileage...which changes things quite a bit (since in those two cases the discrepancy could be 1% or 10%). I mention this since you need to take note that there will ALWAYS be a discrepancy between a GPS device and a vehicle’s odometer value.

The digitally calculated value of the satellite logged trip will never match up to a vehicle’s physical odometer.

This is due to simple mechanics really - the value from a GPS assisted device is calculated digitally using a collection of data points logged. It adds up the distance between the points and thus you are presented with the total distance travelled. The vehicle’s odometer works very differently...this is received through a mechanical system and is subject to various factors, such as road conditions, wheel circumference, friction, driving style, etc.

A simple example - A driver stops at a traffic light and the next traffic light is exactly 400 M away (a ‘quarter mile’) - the driver races someone to the next light, wheel-spins away and brakes hard to stop at the next red light, skidding to the line. The logbook will record 400 M....but the odometer shows 425 M (because the car wheels turned and accumulated 50 M before the car actually moved (wheel-spin) and the car skidded for 25 M with the wheels locked. Thus the odometer thinks 50 M was driven before the car actually moved and didn't record the 25 M while the wheels were not turning. This equates to 25 M further than was actually travelled...if the wheels didn't lock up when the vehicle braked hard, it would have recorded 450 M. But in reality the vehicle still only travelled 400 M.

A simple test is something we have all seen -if you have a Garmin or a TomTom GPS navigation device, drive at exactly 100 KM/H on your car’s speedometer and check what speed you are driving according to the GPS device -probably somewhere around 90 KM/H. Now translate that to kilometers driven and if you drove exactly 100 KM/H for one hour, you would expect to have driven...100 KM. You probably drove +-90 KM in reality.

The GPS calculated distance and speed is always more correct than any mechanically generated result due to the factors mentioned. The aforementioned factors need to be taken into consideration by employees and management / payroll administrators alike - obviously any extensive discrepancy should be reported to and will be investigated by Little LogBook Support to ascertain whether or not there is a hardware issue that caused the discrepancy. 


Generally an odometer difference of between 3 - 4% is an expected value and anything over that is usually due to something else (user intervention / intentional sabotage or improper use of the software and/or hardware).