The second Battle of El Alamein October 1942 was fought without American troops but may have involved US hardware. This battle was referred to as 'the end to the beginning' of WWII by Churchill and was the first major land battle victory for British and Commonwealth soldiers. After El Alamein the allies did not lose another major battle.
scotstone is correct and very accurate, but i'd just like to point out, that if it wasn't for General Auchinlek, who fought the Gemans to a standsill at the first battle, the second wouldn't have been won, it was his preperation that won the second, not Montgomery's.
he was twice the field tacticion and general that Montgomery ever was.