Just put New axle under the bee, I'm no mechanic but have made it through the process all the way down to bleeding the brakes. I have UFP SINGLE CALIPER SYSTEM ON A SINGLE AXLE TRAILER. The lines have been taken apart in several places so I'm sure I have large bubbles in several spots. The tongue of the trailer has been kept about 6 inches lower than the axle during the changeover. If that makes any difference.