It's just so I can put power down to both wheels, nothing major, and I didn't want to put gears in because I don't want to loose any gas mileage. No offence but who are you to say when I should put one in or not?

 

to put in a new carrier you need new bearings and races, and a press to get them on the carrier. its still possible in your garage just take the carrier up to a parts place that has a press and have them press the bearings on, and your set to re install