If you have a flat or a blowout, that spare tire in your trunk can get you back on the road again. Full-size spares have no driving restrictions, but if your spare is one of those compact temporary spares also known as donut tires, then you must take certain precautions and alter your driving style. Make sure to keep in mind the following when driving on a spare tire.
1. Restrict Your Speed
After installing your temporary spare, which should be at 60 psi, remember to restrict your speed while driving on the odd-sized tire. Tire manufacturers usually recommend a speed limit of 50 mph. If you’re driving on a spare tire on an interstate, stay in the right lane to allow other drivers to pass. In some states, but not in all, you’re allowed to activate the hazard lights to warn others while driving an impaired vehicle.
In addition to restricting your speed, limit your driving range on a compact temporary tire to 50 to 70 miles, or the distance outlined in your owner’s manual. One of the reasons to limit driving distance is the toll a donut spare takes on a car’s equipment, including the differential. The differential sends power to the wheels from the transmission and also allows the left and right wheels to turn at different speeds, as needed. Donuts make the differential work harder under certain conditions and can lead to a breakdown, especially if your vehicle has a limited-slip differential.
3. Know the Affected Systems
Soon after you place a donut spare on your car, the wheel-speed sensor might detect the difference and light up your instrument panel with brake and ABS (anti-lock braking system) warning lights. This happens because your compact spare may rotate faster than the other tires to keep up, and the sensors detect a problem.
4. Handle With Care
With the ABS system compromised and traction control also affected, you need to handle your car with extra care. Keep the cruise control off and anticipate longer stopping distances, just as you would with slick or ice-covered roads. Take curves with extreme caution.
Changing a spare can be a hassle, but a jack that utilizes a quick-lifting hydraulic system will make the process safer and less frustrating. When you’ve reached your destination, remember to check the donut for damage. It’s better to replace temporary compact spares than mend them.
Check out all the steering and suspension parts
Photo courtesy of Flickr.
Matt Keegan has maintained his love for cars ever since his father taught him kicking tires can be one way to uncover a problem with a vehicle’s suspension system. He since moved on to learn a few things about coefficient of drag, G-forces, toe-heel shifting, and how to work the crazy infotainment system in some random weekly driver. Matt is a member of the Washington Automotive Press Association and is a contributor to various print and online media sources.