Flat tires from roofing nails are no surprise

Q: I have had two flat tires this summer. Both from nails. One was a roofing nail and the other was a 2 3/4-inch spike. In both cases only the head of the nail was showing on the tread. How does a nail lying horizontal on the pavement re-position itself, so the point drives itself into the tire and leaves only the head showing with (in my case) over 2 inches of the spike going straight into the wheel? I guess I'm lucky they weren't in the sidewall. - T.K., Lombard, Ill.

A: Like many little kids, roofing nails like to stand on their heads. Getting one in your tire is no surprise, especially if you have replaced your shingles recently. (We have and, despite their best efforts, the roofers left us several souvenirs.) As for an eight-penny (8d) nail, that is a mystery. But there is no mystery as to the depth of the puncture. Driving around on a nail drives it home.

Q: Regarding your article about having to download an owner's manual for a Chrysler. How about a way to view this manual on the TV screen in the center of my dashboard? Now that would be a helpful improvement! - R.F., Lakeland, Fla.

A: What a great idea. I can envision one argument against this, though. Reading a PDF file from a thumb drive while driving would be tantamount to texting (a big no-no) so a safety algorithm would be necessary. If you can only view the file while parked and in the accessory mode, why not simply use a laptop?

Q: I drive a 2017 Jetta with a 1.4-liter DOHC turbo direct injection engine. It is my first car with a turbo, and I love its performance. What if anything can I do to maintain the turbo? - E.K., Boynton Beach, Fla.

A: Modern turbochargers are robust and need no special care. But if you have been hammering the car hard, such as on the racetrack, I suggest allowing the engine to idle about a minute before shutting it off to allow the turbo to cool a bit.

Q: When my car was still under warranty, an Audi service adviser shamed me for having my oil changed by an independent Bosch-certified mechanic using the gravity method. He advised I would void my warranty unless the dealer changed the oil using vacuum extraction as recommended by Audi. Now that my warranty coverage has passed, what's the real advice on this matter as I prepare for my next oil and filter change? - M.P., Fort Lauderdale, Fla.

A: You can't go wrong pulling the drain plug. Some shops push the extraction method because it is quicker. But there is a risk of oil dripping from the hose during removal and a potential for an engine compartment fire. Remote? Maybe. But I am old-fashioned.

Q: I own a 2016 Ford Edge with the 2.4-liter engine. Last week I went to my dealer for an oil change and safety inspection sticker. One adviser said I needed pads and rotors. The person that brought me the bill said I had at least 5,000 miles left on them and that I was almost in the red and when you get in the red, they wear down fast. I don't even know what "in the red" means. Should I have my brakes checked somewhere else? - J.H., Boston

A: I presume that the service writer was using sports jargon to tell you that the brakes were nearing the end of their service life. Since you were getting a safety inspection (to get the sticker), the brakes passed the inspection; they are fine. If you are worried, have the pads inspected by any technician after 5,000 more miles. The pads will not wear more quickly.

Bob Weber is a writer and mechanic who became an ASE-certified Master Automobile Technician in 1976. He maintains this status by seeking certification every five years. Weber's work appears in professional trade magazines and other consumer publications. His writing also appears in automotive trade publications, Consumer Guide and Consumers Digest.

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