any sat nav that can keep you off the country lanes

[carlovers]

Hi Guys i have a garmin 310 which you can say if you are a car, bus, lorry, bike etc. but it still takes me down the narrow lanes of bucks and oxfordshire when im out selling which drives me mad. Im looking for a new sat nav does any keep you off these.The nuvi can keep you off the"highway" but not lanes whatever you in put.