Just wondering what I'd need (parts wise) to successfully re-gear my 3.73 with L/S explorer rear end to a 4.56 ratio. Do I just need the pinion and ring gear set or is there other stuff as well! Thank you. (If there's a how-to guide somewhere that would be great)

 

You'll need the install kit which comes with shims so you can get the mesh right. The master install kit should come with everything you need. If you've never done one yourself, getting the mesh perfect sucks. You'll also need a crush nut for the pinion gear when you reinstall it. Some kits come with it, some don't. Don't forget the friction modifier if you're swapping with a limited slip diff.

You'll need to have the ability to torque correctly up to like 250 or 300 lb ft if I remember correctly for the pinion nut.

I re-geared my mustang from 3.31 to 3.73 and I removed the entire rear axle from under the car to make it easier to work on. once I reinstalled everything, I had a slight noise when turning from the mesh not being perfect...immediately took it to Ford who charged me $750 to fix it. They initially told me it would only be $750 for the complete install. So If you're not 100% confident is getting it right, let someone else do it or you'll cause yourself a bunch of heart ache. Not to mention, if you botch it too bad it can destroy itself. Now you have re-purchase everything and probably even get a tow.