Front D30 and Rear D35 4.10 Gear Set w/ Install Kits (00-01 Cherokee XJ)Increase your lifted Jeep's performance and take your rock crawling experience to a whole, new level with Rough Country's Ring and Pinion Combo kits. Our durable aftermarket gear upgrade combo kits come with everything you need to regear the front and rear of your vehicle and breathe new life into your lifted Jeep. Ring and Pinion Gears help your vehicle take power supplied from the drive shaft and push it out to through the axle shafts to the wheels.