Different vehicles have different capabilities. I believe that the Abrams comes with it's own atmosphere and it might night die to molotovs.
Remember there is no single solution to a problem.
Most modern tanks are totaly sealed and impervious to Finnish Grenades (Molotov Cocktails) but if a hatch is left open or initial damage done to the tank they can work.
Other vehicles would be vulnerable but in order to effectively take out a tank a better civilian method would be to use Dynamite or similar explosives to knock out the tracks.
The best way to fight an Abrams however is not to fight it. Allow it to pass and within 6 hours it will have to refuel, which means you ambush the refueling trucks and leave the tanks stranded. They then become bunkers that can be knocked out with explosives or swarmed with infantry.
