A run flat tire might sound like a good idea. Who wants to pull over to the side of the road to change a flat? You may have never heard of run flat tires and I must admit I had no idea that I was the owner of such a technological advance.
We were up North (that is Minnesotan for we were at the cabin) and I thought one tire looked a little flat when we preparing to drive back to The Cities (Minneapolis and surrounding suburbs). Despite growing up on a farm I admit to having very, very limited mechanical skills. However, driving on gravel roads during my formative years meant I am very experienced changing tires. I thought this would be a simple matter of driving to a station and putting a little air in the tire. Our new car seems less sophisticated than our last. The Town and Country would let you know when a specific tire was low and provide the tire pressure for each tire. We abandoned what I thought was a great van for a Toyota Sienna because it has all wheel drive. Again, this is an Up North thing. All wheel drive is helpful when driving out of the woods after a snow storm.
So, I make it to the gas station, but had no way to evaluate just how flat my flat tire is. I decide to purchase a tire gauge. Everyone should carry one of these. I make my purchase and test the tire I thought was flat and the gauge will not register a pressure reading. This is the point at which my lack of mechanical awareness and common sense become a problem. I decide the gauge must be defective, inform the clerk in the station of this discovery, and am given a new gauge. The new gauge also registers no pressure which leaves me completely befuddled, but also a little embarrassed. I am about to ask the clerk for help when I decide to try a different tire. Sure enough, the gauge does work. The low tire seems to have no air which seem impossible based on my understanding of auto mechanics. I try to put some air in, but I can hear air escaping at the same time. Giving up on the gauge issue I decide to attempt to drive to the next town where I hope to find someone to fix my tire.
The car seemed to function reasonably well given I was driving on a tire I thought had no air pressure. I have been cautioned against driving on a flat and ruining a rim when young so I was careful. I did get to the next town, did find a full-service garage, and did get the tire off the car. However, I then learned that the tire could not be fixed (something about it being a split and not a puncture) and was also told that it was a run flat tire. One of the supposed benefits of having run flat tires turned out to be a significant problem. Run flat tires are evidently built to run for 50-100 miles even when punctured. The side walls are extra stiff. A secondary benefit of run flat tires is that having such tires evidently means cars no longer need to carry a spare or the equipment to change a tire – less weight, better gas mileage. It took some convincing. The owner’s manual says I have a spare. I looked everywhere a spare might be kept. Sure enough, I could find the location on the floor of the car that provides a way to attach a spare under the car, but the spare and the mechanism were not installed on my car.
So, here is the deal. A run flat is good for 50-100 miles. The recommendation is 50 miles. I am 140 miles from The Cities. I know I have run 25 miles already and I am uncertain of how long the tire was flat before it was discovered. One of the reasons you and I have probably never heard of run flat tires is that few cars use them. This means you cannot find them. This means you are likely to find yourself stuck for a day or so if you should ever have a flat in many parts of the country. Most folks, simply as a function of how many people live in populated areas, would be OK, but those folks living elsewhere need to look for a motel and have the local garage have a tire ordered. We were lucky. The garage we found gave us a loaner car at no cost. Such experiences are on the positive side of what living Up North can mean.
We ran into one more issue with the tire. One reason cars with run flat tires and all wheel drive do not carry a donut spare is that the tires must be within 3/16 of each other in tread depth or risk damage to the transmission. Of course, a donut tire is very different in size. If the 3/16th standard cannot be met, the recommendation is to buy all new tires. This would mean we would lose approximately 25000 of wear on our remaining tires and have to spend approximately $1000 for a new set of tires. I am really tempted to change back to traditional tires. I could carry an extra tire or just assume I could find a replacement far more easily should the need arise.
I would think a dealer would tell you about run flat tires and explain the advantages and disadvantages. This was not our experience and I mildly resent the oversight (Toyota of Saint Cloud). I am old enough to be beyond taking myself too seriously. Asking a clerk for a second tire gauge and suggesting to a garage guy that there must be a spare tire are now just kind of funny. Experiences like this make for good stories. Check your tires.