Let me save you some effort, we've established this through years of experience and a number of incidents: Always use secondary supports, lifting equipment is not fail to safe, both the screw-thread and hydraulic variety often have mechanical safety measures that should work, but don't always. Never use wooden blocks to support vehicles or their components, wood can fail, and its really difficult to inspect or certify as suitable. Always have these rules and max-loads really visible on equipment, something as simple as the load rating being less than clear has caused overloading and failure of axle stands (last role, not this one). PM me if you want some more information. JC