Letter Re: Basic Mechanics Skills and Knowing Vehicular Limitations, Part 1

James Wesley,
In reply to Z.T.’s article, Basic Mechanics Skills and Knowing Vehicular Limitations, Part 1:

In general, while Z.T.’s post concerns tire maintenance, you should think “maintenance” on all fronts. Are you personally familiar with how much oil your vehicle eats per thousand miles? Are you familiar with your current, average and customary fuel mileage? Any diversion from the customary indicates a potential problem. Provided you’re aware of what “customary” is on all fronts. Are you also checking, and familiar with, all fluid levels? Of all kinds? Simple preventive stuff. Find the problem before it becomes an actual problem.

And, as Z.T. points out, how aware are you of your tires’ health? Or what it is you need to change a tire quickly and efficiently, or understand tire physics?

My rules of thumb, at least for those with steel wheels:

Every 10 degrees of ambient temperature difference equates to about 1 pound of tire pressure. Ten degrees higher? 1 pound higher. Ten degrees lower? 1 pound lesser. Whether “in-service” or as a spare, each ongoing month also equals to about a 1 pound loss per month, generally. You should be checking your in-service tires regularly. Again – are you noting any diversion from the norm? As for spares? It can be difficult to monitor them. So look at the Maximum Pressure rating on the side of your spare and inflate them to that safe maximum. You can always bleed it down to the recommended in-service inflation rating later, should you need to use it. Of course, that means you also carry a tire pressure gauge in the glove box. Carrying with you a small tire compressor that plugs into your vehicle? Gold! For yourself, as well as for others you can help along the way. No “grid” needed! No quarters needed!

And I made mention of steel wheels specifically, because if you have any sort of “alloy” wheels? Any and all long terms bets are off. As compared to true steel wheels, these alloys can be wild cards. When cast, there are all too often too many “porous” castings – where you have air leaking regularly from at least one tire through the “leaky” wheel itself. Got alloys? Get a tire gauge and use it regularly! Know your one leaky tire and pay attention to it!

An “alloy” tale: As you can tell, I’m aware and “prepared”. I’ve made sure my vehicle’s jacking components are actually there, I’ve done at least a “dry run” with them, I know where my jacking points are, I’ve got ponchos, adequate lighting, and have supplemented with additional crowbars, padded kneeler devices, tarps, tools, etc. I routinely take 1,400+ mile trips. I was prepared. Or so I thought. Yet still found myself unprepared one day. On a long road trip, and in the middle of nowhere (of course), I had a flat. No biggie. Been there, done that.

Problem was the alloys. Your alloy wheel is in contact with different and lesser metals on the spindles and hub. Dissimilar metals in contact? Along with moisture and/or salt? Electrolytic corrosion. Even though I religiously rotate my tires frequently? When I had my flat, that wheel was virtually “welded” to the hub. And I’m a big guy – yet nothing I could do would loosen it. I even thumbed the nuts back on and ran the car back and forth jarring the brakes to try to break the wheel loose. God help me, I eventually crawled under the jacked-up and swaying front end, trying to kick the wheel outwards, to no avail.

Thanks to my trusty cell phone and the kindness of telephone strangers, finally found the nearest actual “service” station, 50 miles away. At that point, I knew what I needed, and what it was I didn’t have. Merely, a good-sized length of 2×4 and a sledge hammer. And that’s all it took once the kid showed up. Yet I paid dearly for my rescue. At least the kid that came out finished the job, for which my back was eternally grateful!

I now carry a 20# sledge hammer and a 3-foot length of 2×4. That length of 2×4 allows you to place an unyielding mass as close to the inside hub center as possible, and then evenly spreads the impact from your sledge hammer outwards. Your sledge hammer, which will provide a far sharper impact outward than your own desperate boot-kicks under a jacked-up vehicle in the middle of nowhere, while traffic passing traffic is blowing by at 70 miles per hour. – Dave L.