Yukon ring and pinions are forged out of 8620 Steel. They are known for their strength and reliability. This is a high performance Quiet gear, perfect for any vehicle from Stock and beyond, it will handle the rigors of big tires or high horse power. Fits low pinion applications Not TJ/WJ: Jeep CJ, ZJ pre 96.5. Pre 96.5 ZJ requires ZJ master install Kit, and will be converted from crush sleeve design to solid pinion shim design. Master kit also has required adapter outer pinion bearing.