My family and I went on I-75 last month and had no problems with construction going and coming back in any state or city. Besides that after crossing the border into the United States you will go threw a detour in Detroit to reach I-75 South, however it's cleary marked and you should have no problems with that. Now driving back home they changed the exit for the Bridge to Canada which is now exit 47A because they are doing major construction in Detroit, so you have no choice to get off I-75. However since you need to use that exit to get back into Canada it won't effect you.