Lug nuts are the bits of metal that keep your wheel rim securely set into your vehicle's axle rig. Loosening and tightening these are both the first and last steps in changing tires so ensuring that you have adequate tightness is important in the stability and safety of your ride. Nuts that are too loose might result in a wobbly ride, and your wheels could come off. Nuts that are too tight might be difficult to remove, though, and could even damage your rims. Here's how you tighten a lug nut.
- The first thing you need are the right tools. Make sure that you have the right caliber wrench with the correct specifications. When changing tires, one usually uses an X-shaped wrench called a "torque wrench." More often than not, your auto dealer would have already included a torque wrench in the trunk, along with either a hydraulic or screw-type jack.
- Raise your car on a hydraulic jack to gain access to the tire rig. Cars have different numbers of lug nuts so make sure that you're not misplacing any while working on this task. Most compact sedans have four nuts. MPVs and minivans usually have five. SUVs and bigger vehicles have six, eight or even more.
- If your wheels have hubcaps that cover the lug nuts, you have to pry these off first, with a flathead screwdriver or with the appropriate tool that comes with the car. You can now attach the lug nuts by hand onto the wheel using a star-shaped pattern across the tire. First put on the top lug nut, then the bottom, then the left, then right. Put them on with the least possible pressure and keep it even throughout the entire tire. This ensures that the wheel is well balanced.
- After you've screwed on all the lug nuts by hand, proceed to tighten the first bolt, again with your hands. Tighten the rest of the bolts in the order in which you attached them to the tire, again following a star-shaped pattern to ensure that the weight and pressure are evenly distributed.
- Release pressure from the hydraulic jack to let your car down. Make sure there are no tools or people underneath the car, before doing this. Using the torque wrench, tighten the bolts on your wheel using the same star-shaped pattern. Use moderate pressure first, making sure the pressure on each lug nut is the same, to make sure pressure and weight is equal across all nuts.
- Finally, tighten the nuts once more with full pressure, using the same star-shaped pattern.
For the last step, you usually need to attach an extender to the torque wrench so you can use the leverage to apply more pressure. Some mechanics actually use their body weight and step on the lever for more pressure. However, auto manufacturers don't recommend this, as it might actually cause more harm than good.
Once your tire is secure, you should now be ready to replace the hubcap, and pack away all your tools in the trunk. You should recheck tightness after running your car a few miles, or when you get back home to your driveway, just to be sure nothing has come loose in the course of your trip.