Travelling through France at the mo. My van is 3.8 tonnes. The SatNav says I can only do 90 kph on alll motorways. On a detour round Rouen was on a stretch of dual carriageway where the SAtNav said I could do 110 kph. Then on A 10 south of Tours there was a sign at the side of the motorway saying the limit for over 3.5 tonnes was 110. But the SatNav still said 90. So is the SatNAv wrong and can I do 110 on the motorways?