3 Flats In One Day - Why a Spare Tire and Portable Air Pump Are A Must

A Car Talk vehicle tester had three flat tires on two separate vehicles in two states in just six hours. Here’s why having a solid plan for tire trouble is essential.

As vehicle testers, we drive a variety of vehicles in a variety of situations each week. This past week your author had three flat tires in one day, which brought his flat tire total for the year to five.

Starting the Day With a Flat

The first flat tire was in a media test vehicle. By 10:00 in the morning the day it arrived, the Tire Pressure Monitoring System, TPMS, was illuminated politely saying the passenger rear tire was below the setpoint. This happened in the Metro Boston area. There was no visible damage to the outside of the tire upon inspection, and the vehicle felt normal in driving. The TPMS illuminated at about 25 psi, down ten psi from its proper setpoint. That flat ended up being a slow leak of about three psi per day.

The Second Flat In One Day

The second flat occurred 100 miles away later that day in a Subaru Forester while the first vehicle was out of service awaiting repairs. The Subaru’s TPMS system reported a problem, but the Suby’s alert is general. It just tells you something is wrong with one of the tires. It was easy to spot this one. The drivers’ side rear tire was noticeably lower than the others. Luckily, there was a tire repair store just a few miles away. Using a portable 12-volt pump carried in all of our test vehicles, we inflated the tire up to and above the setpoint of 30 psi. We headed off to the tire repair store with a tire audibly hissing air.

Lucky Flats

If you have a flat in the outer or inner tread block, roughly 40% of the tire footprint, reputable tire stores will not repair the tire in Hillsboro, New Hampshire, patched and plugged the tire ten minutes later. What luck!!

The Bonus Flat Tire

Following our pit stop, the tire technician circled the parking lot in the car with the repaired tire, re-checked the torque setting of the lug nuts, and said, “You’re all set.”

We then asked if the technician had checked the pressure in the other tires. The reply was, “Nope.” Indeed, another tire was also low, and there was a drywall screw sticking out of it. Upon inspection with a soapy water mixture, a leak from that screw was confirmed. Back into the shop went another tire. Luckily, this second tire was also repairable.

Air Compressors and Spare Tires

Portable air compressors cost around $50 on Amazon and can inflate a tire in a pinch. Thus enabling you to travel a few miles to a nearby tire repair store, or at least get you off the highway and down an exit ramp to a safer location. If you have a long ride to a possible repair, or if the tire is damaged so badly it cannot be driven upon, your compact spare tire will be worth its weight in gold.

Battlefield Dressings

Repairing a tire on the side of the road, unless you are a tire technician or mechanic, is impractical, but just in case, we carry a plug kit in our vehicles. The kits cost under $20 and they are flat, so they don’t occupy any storage space. Theoretically, a person could plug their own tire puncture in a situation where getting to a tire store wasn’t an option.

Another tool kept in our test vehicles, since more and more come without a spare, is a tire sealant kit. These operate by pumping in some goo followed by inflating the tire. The goo fills the hole, and you are back in the game until you find a tire store. Be aware, the people at the tire store will then curse you for using the tire goo option. Our confidence that the goo won’t be hard as diamonds between November and May in New England winter is zero.

AAA Card Is a Must

Despite carrying an arsenal of tire-repair tools, a smart driver’s most trusted resource is a AAA membership card. In the event you do need to employ your compact spare, call AAA and let them mount it. AAA technicians are extremely knowledgeable, helpful and respond very quickly. If one of the lug nuts is frozen, or some other calamity befalls you during the flat tire event, at least AAA can tow the vehicle away as a last resort.

How Many Flats Happen Each Year?

We reached out to John Paul, AAA Northeast’s spokesperson, who is also a certified mechanic. John confirmed that AAA is as busy as the group has even been with tire-failure calls. There are approximately 220 million tire failures in America each year. That equates nicely to about one per vehicle on the road. If you haven’t had a flat tire in quite a while, logic would indicate that your turn may be overdue. The time to plan ahead is now.

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