grinding noise between 30 and 40 mph only??????

hi there i own a silver vauxhall vectra 1.8 and iv had the vehicle for about 4 months, it starts fine and drives great but i get a sort of grinding noise when i go between 30 and 40 mph and it also makes my brakes feel stiff like im grinding metal. below 30 mph its fine no issues and above 40 mph its fine no issues nothing breaks are fine took them off and inspected them no wear or tear onthem and if im travelling between 30+40 for like 2 mins the ABS light comes on dashboard and i no longer hear the grinding or have issues with my breaks.. can anyone help me plz i know nothing about cars. i am contactable on e mail at lbeevers40@googlemail.com for any suggestions