Combine flour, baking soda, baking powder & salt in a large bowl.
Blend eggs, sugar, butter, vanilla, lemon extract & lemon juice in a medium bowl. Pour wet ingredient into dry ingredients & blend until smooth.
Add oil & mix well. Pour ingredients into a well-greased 9x5-inch loaf pan. Bake for 45 minutes or until a toothpick stuck into the center of the cake comes out clean. Make the lemon icing by combining ingredients in a small bowl with electric mixer on low speed.
When the lemon loaf is cool, remove it from the pan & frost the top with the lemon icing. When the icing has set up, slice the loaf into eight 1-inch-thick slices.