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Black Friday shopping for new tires
I spent a portion of Black Friday waiting patiently in the frigid cold to take advantage of a deal on tires. For months now, I have been keeping a close eye on my tire tread wear. For awhile there, I thought I could hold out until the spring; however, as some forecasters predict wet El Nino-related weather will begin next month, I felt it may be safer to replace my tires sooner than later. After all, the tread was just shy of the indicator line. Healthy tires should be inflated to the specification in your owners manual. The tread should have more than 2/32 inches of depth. Check tread wear by slipping a penny or quarter into the tire crevice with the president's head upside down and facing you. If you can see all of the president's head, it's time for new tires. Tire health can mean the difference between reaching our destination safe and sound or risking hydroplaning and crashing on soaked and/or flooded roads. Hydroplaning occurs when tires lose contact with the road due to lots of water between the tires and the road. Tread depth helps determine how good a grip your tires will have on the road in average conditions. The deeper the tread, the better. Part of my decision to replace my tires was that I had a slow leak in a tire, requiring increasing trips to the air pump each month. Improperly inflated tires make the tread wear down faster. It also means it's easier to hydroplane at higher speeds. The one tire I suspected of having the slow leak had less tread than the remaining three tires. According to the National Highway Traffic Safety Association, under-inflated tires have more tire touching the road at lower speeds of less than 50 mph. "However, hydroplaning does not occur very often at speeds below 50 mph, unless there is deep water on the road, the agency reported in a report on tire pressure monitoring systems, at http://www.nhtsa.gov/cars/rules/rulings/TirePresFinal/FEA/TPMS5.html. "As you get to about 55 mph and the water pressure going under the tire increases, an under-inflated tire has less pressure in it pushing down on the road and you have less tire-to-road contact than a properly inflated tire as the center portion of the tread gets lifted out of contact with the road." When speeds rise to 70 mph and beyond, and water depth increases due to a severe local storm with poor drainage, poorly inflated tires could lose 40 percent of its tire-to-road contact area compared to properly inflated tires, the report continued. "The higher the speed and the more under-inflated the tire is, then the lower the tire-to-road contact and the higher is the chance of hydroplaning," the report said. After making my Black Friday purchase, I explained to my kids the significance of this rather strange gift I gave us all this holiday season -- the gift of peace of mind. Smarts appears Mondays. Follow it on Twitter and Facebook. Submit questions to those aforementioned social media sites or to streetsmarts@ santacruzsentinel.com. Please include your name, city of residence and a phone number where you can be reached.