Conduire is a transitive verb, see : http://www.cnrtl.fr/definition/conduire .

The sentence

Je pourrais conduire à Montréal.

means

I can drive inside Montréal.

The correct sentence is:

Je pourrais conduire jusqu’à Montréal en 7 ou 8 heures.

or,

Je pourrais conduire cette voiture [cette personne] à Montréal en 7 ou 8 heures.

In addition to M42 answer, conduire vers is also commonly used, but only to express direction. For example, it’s possible to use vers followed with a city name; that would not mean that this city is your destination, just that it is in your general direction.