4. These beefy Yukon axles are made of 1541H alloy steel, which are only a couple of steps below chromoly in strength but much more reasonably priced. A 1541 axle is approximately 55 percent stronger than the usual 1040 axle material, and at least 15 percent stronger than the Ford OE 10.50. We also opted for Yukon's prepackaged wheel bearings and seal kit. Our '97 was the earlier unit with 1.625-inch-diameter bearing surfaces.