technically you are NOT a US resident, you're just a temporary resident.
I think there is a law against non-citizens and non-LPRs taking US registered cars across the border, there was someone else here a while ago that said she was stopped at the border and not allowed to cross with the rental car.
I am a Canadian in Michigan also under TD status. My husband and I rent cars regularly from Enterprise for our trips back to Ontario, and we have no problems whatsoever. As mentioned, you must inform your rental agency that you will be taking the car out of the country.