Revolution Gear and Axle D30, 4340 Chrome-Moly US Made Front Axle Kit for 07-15 Jeep Wrangler JK Sahara and X Model, 30 Spline Upgrade kit with ARB Air Locker. All Revolution, Jeep front axle kits come with 2 US Made 4340 Chrome-Moly inner axles, 2 US Made 4340 Chrome-Moly outer stub axles, 2 Dana Spicer 5-7166X U-joints and 8 Full Circle Snap rings to hold it all together. Revolution uses the large â€œ1350â€ style u-joint for all if our Jeep application. Using the substantially larger 1350 u-join provides a substantial strength increase over the smaller 5-760X joint and allows extra clearance for tighter turning. All Revolution Axles are backed by a fantastic lifetime warranty against failures, including but not limited to U-Joint failure.