Driveway Crack Filler Large

How should i fill in narrow but "deep" driveway cracks and he reason to use the separate crack sealer for the top 1412" of the cracks, again, is if you use grout it will crack away the next time the crack moves, andjust pop out you need a flexible compound like the latex crack filler at least at the top and can be used full depth but pricey to do so on large cracks because it will.