by Pat Goss
Here’s something that’s pretty basic, a flat tire. Now you would think that that would be just straightforward, but it can actually be dangerous and it can be confusing. You see cars today, well, they don’t all have spare tires. They may have no spare, yet come equipped with an air pump and some puncture sealer.
Well, even if you do have a spare, how could it be dangerous? Well, you’re not going to have a NASCAR jack to deal with, but rather you’re going to be stuck with something like this, a scissors jack. Well, if you follow all of the rules and everything, these will get the job done, but you have to be extremely careful, especially if you’re on soft dirt or anything like that, because these can tip over, they can collapse. In general they can be dangerous. The best way to change that flat tire is with your cell phone. Call the roadside assistance and have them do it for you. That’s safe.
Now even things like rotating tires can lead to problems with the car. The most typical one is a warped brake rotor. That’s going to make the steering wheel shudder when you apply the brakes at high speed. Not a nice situation, plus it can be expensive to repair.
Now over the years technicians have historically used air impact guns. Now these things produce a lot of torque, they’re fast, and they do a good job, but when it comes to wheels, well, they should never be used, at least not with one of these conventional sockets.
Now what we’ve accepted in the industry over the years are what are called torque sticks. These limit the amount of torque that the impact wrench applies to the lug nuts. That’s good if they’re used properly, but now we’re seeing technical service bulletins warning against one of the common practices that people employ, and that is they’ll put the first lug nut on, they’ll hit it with a torque stick, tighten it up, and then go on around the remaining lug nuts. Well, that first one being tight is a no-no. All of the lug nuts have to be tightened gently, finger tight, just a little bit beyond finger tight actually, and then they have to be properly torqued. If you don’t do that, the first one will be severely over tightened, and that will warp a brake rotor. If you really want to be 100 percent safe, a manual torque wrench is the best way to go. But again, finger tight first on all of the lug nuts. That way you’ll avoid warped rotors and pulsating brakes.
If you have a question or comment, write to me. The address is MotorWeek, Owings Mills, MD, 21117.