Originally Posted by 2millionquest

Maybe, if everything goes exactly perfect. Clearing customs and immigration and rechecking bags for your onward flight takes about 45 minutes to an hour. Then you have to transit from T5 to T3, which normally takes about 10 minutes, but can take a bit longer if your timing is off on catching the PeopleMover. Then you have to get through security again at T3. That can take anywhere from 10 to 45 minutes (depending on the usual factors). Then plan on another 10 minutes to get to your gate for your domestic flight (more if the domestic flight is at H18 or something like that).

I know ORD like the back of my hand (used to volunteer there ferrying foreign exchange students from international to domestic flights and vice-versa before 9/11), and I would absolutely not recommend anything under three hours for a transfer like that.

Getting from T5 to T3 confuses the heck out of people who've never done it before. It's actually quite simple, but the signage is horrendous. It's been about two years since the last time I did it, so maybe someone who's done it more recently can chime in and say things have improved, but again, I'd really strongly advise against the 1h45m time frame. To my mind, you're just asking for trouble.