What Are Wheel Torque Specs?
Rotating tires and installing new wheels are jobs that many of us can handle ourselves. Within minutes, you can complete the task and get back on the road. But doing the job right requires more than just securing your wheel components with lug nuts or bolts. Every wheel must be tightened according to the recommended wheel torque specs based on the vehicle’s make, model and year. If this isn’t done correctly, a potential catastrophe awaits.
Wheels and Lug Torquing
Simply put, wheel torque represents a rotational force that is applied when you tighten a lug nut or bolt. When this is done right, you avoid stretching the studs, over-tightening the hardware or stripping the fastening threads. Tightening the lug nuts and bolts correctly also reduces the chance of warping the brake drums, rotors or hubs.
Torque specifications are found in your owner’s manual, and they refer to dry threads only. This means no dirt, corrosion or oil should be present, including lubrication. This point is critical because the friction by which torque is measured must come from clean hardware seats. Lubricating the threads and seats would skew the friction as measured by a torque wrench at the lug seat, causing an imprecise torque readout that might adversely impact the hardware.
Using the Wrench
Using a torque wrench involves adjusting the bolt at the bottom of the wrench and then twisting the bottom part of the wrench in place according to graduated markings etched in the shaft of the tool. For example, if the torque measurement requirement is 90, adjust the bottom part of the wrench to line up the 0 with the 90 to create 90 pound-feet of torque. Once it’s set in place, tighten the bottom bolt to secure the reading. There are also digital torque readers that can make this job even easier.
With the vehicle secured in place by a lift and chocks, align the wheel with the stud bolts to set the wheel in place. Begin screwing each nut into place by hand as far as you can go. Once you’re done, lower the car so the wheels don’t spin when you apply force, and use your torque wrench to complete the job (typically two clicks of the torque wrench for each nut is sufficient). Be sure to follow the star or alternate pattern as outlined in the owner’s manual. That pattern will be determined by the number of stud bolts present.
Torque Wrench Considerations
Never drop a torque wrench, as that can affect wrench calibration even if it doesn’t show signs of damage. One way to confirm its calibration is to compare the dropped torque wrench with one that hasn’t been dropped and observe whether there is a difference in tightening the nuts. But few of us have two wrenches of this kind, so having the wrench professionally recalibrated is usually the solution. Even if you never drop a torque wrench, a regular recalibration is sensible.
Lastly, if you’re installing a new set of wheels, drive the vehicle for 50 to 100 miles and then retorque the wheels. Metal compression, elongation or thermal stress can affect the wheels as they are being broken in, so wait until the wheels have cooled to check the torque value.
Check out all the hand tools available on NAPA Online, or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on wheel torque specs, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.
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Matthew C. Keegan View All
Matt Keegan has maintained his love for cars ever since his father taught him kicking tires can be one way to uncover a problem with a vehicle’s suspension system. He since moved on to learn a few things about coefficient of drag, G-forces, toe-heel shifting, and how to work the crazy infotainment system in some random weekly driver. Matt is a member of the Washington Automotive Press Association and is a contributor to various print and online media sources.