I haven't actually replaced a D30 hub, however, I have done a D30 axle U-joint which is a very similar body of work to what you'll need to do. It wasn't difficult. The following should help: D-30 Axle Shaft Removal - 1
Jack up the front of the Jeep, remove lug nuts and wheel, remove caliper bolts and caliper, remove hub bolts (13mm 12pt), remove hub and axle shaft assembly together. You may need a slide hammer if the hub is rusted to the knuckle, or you can back the hub bolts out part way and bang on 'em with a mallet and a block of wood.
If you need to separate the axle shaft from the hub do so with an impact gun or a breaker bar on the hub nut when the assembly is still on the Jeep.
A forum community dedicated to Jeep Wrangler owners and enthusiasts. Come join the discussion about reviews, performance, trail riding, gear, suspension, tires, classifieds, troubleshooting, maintenance, for all JL, JT, JK, TJ, YJ, and CJ models!