If you change a Subaru Impreza transmission and rear differential from a 4.11 ratio to a 4.44 ratio will you have to change the rear hubs as well as the rear axles?

I just can't imagine why you would want to even attempt this. You know that you do need to change the front differential ratio at the same time. You do know that it is all wheel drive, right?. As for changing the rest of the driveline, you will need to ask the supplier of the differential whether the old parts will work with the new differential. There is no inherent reason why you would need to do so.

Incorrect.^^^ The front diff. is built into the tranny. You can bolt the 4.44 trans and rear right in no problems. Ive done it. The reason he would do so is to get a lower gear ratio for more low end, great for racing, rallying, etc. kinda low for cruising the highway, but usable.-Tomcat