My E70 has the most inaccurate speedo/cruise of any car I've had in a few years. With previous cars if I set the cruise to 71k I'll get 70k on the GPS, or 112k to get 110 on the GPS. But with this car it's more like 74k to get a real 70, or 115k to get 110. The car has standard wheels and tyres so there should be no effect from that area.

Is this normal for these cars?