Specific procedures are a must when it comes to installing hub piloted wheel nuts safely— and also to optimize wheel end life, according to the experts at SKF.
• Be sure to always follow the manufacturer’s instructions when working with wheel ends, and keep the following information in mind.
• Prior to re-assembly, check all parts for damage and replace as needed. If a stud requires replacement, also replace the stud on either side. If two studs are damaged, replace all the studs.
• Clean rust, dirt, paint, grease or other debris from the hub mounting surfaces, hub pilots, drum mounting faces and wheel mounting faces.
• Apply SAE 30-weight oil on the last two threads of the stud and add a drop between the nut body and flange so the nut runs smoothly on the threads of the stud. The nut body must spin freely and smoothly against the flange. Be careful to not get lubricant on the mounting face of the drum or wheel. Anti-seize lubricant is not recommended.
• Rotate the wheel so that a hub pilot is at the 12 o’clock position. Place the wheel onto the hub, taking care not to damage the studs. Ensure the wheel is fully seated against the drum.
• Place the outer wheel onto the hub, making sure the hand holes are lined up for access to the tire valves when mounting duals.
• It is critical to tighten wheel nuts to their specific torque specification. Under-torque and over-torque conditions can damage wheel components and result in wheel loss.
• Start at the 12 o’clock position then move to the 6 o’clock position and snug the nuts to 50 ft.-lbs. Many wheel nuts require a torque level of 450-500 ft.-lbs.
• Follow a sequence for snugging and final torque for both eight- and 10-hole systems. For eight-hole systems, the sequence starting from the 12 o’clock position is 1, 2, 4, 6, 8, 3, 5, 7, 9. For 10-hole systems, the sequence is 1, 8, 6, 4, 9, 2, 7, 5, 3, 10.
• All air tools, including torque wrenches, should be calibrated periodically to ensure that the proper torque is applied.
• Double-check that both wheels are seated on the pilots and are flat against the drum, looking for irregularities.
• A settling of components will occur, and the amount will depend upon the component condition and the installation process. Re-check the torque at between 50-100 miles and every 10,000 miles thereafter.
