If you are headed to a car dealership to test drive new cars, be aware that many of today's cars will offer a surprisingly harsh ride. Over bumps, they will be uncomfortable and loud. This is the unfortunate result of style and taste decisions being made by automakers to make the vehicles they offer look better in their eye.
Low Profile Tires
The main issue is tires. Tire technology has evolved and almost every tire on almost every new vehicle today is a "low profile tire." The term refers to a tire that has a very short sidewall. The distance between the ground and the rim of the wheel is very small compared to traditional tires. And because it is very short, it needs to be very stiff to prevent the rim from contacting the ground and to offer the support needed to hold up the tire. This is a layman's description of the way it works, but accurate.
If you are shopping for a top trim of whatever model you like, you will find that the manufacturer has "up-sized" the wheels. If the base trim used 16-inch rims, the top trim may have 18-inch or even 20-inch rims. The tires, of course, will also have a larger diameter. Automakers don't want to fiddle with having multiple speedometer and ABS setting in a given model, so they keep the outer diameter of the tire the same on all trims. They do that by making the sidewall of the base trim taller and the top-trim shorter. This allows the automaker to have multiple wheel packages that all cover the same distance in one revolution. Make sense?
The result of this is that the base trim will ride more comfortably. There is more tire sidewall to absorb impacts over potholes and road imperfections. Sadly, automakers advertise the larger diameter wheels as if they are a benefit. In fact, they are the exact opposite for all daily-use passenger cars and crossovers, and taller wheels and tires are a detriment to the use of any truck or SUV off-road.
Another promotional method all automakers use is packaging features into the higher trims. If you want power-adjustable seats, you won't be able to find them in a base model. instead, you will have to step up to a higher trim and thus, you will get the taller wheels and lower profile tires.
Low Profile Tire Damage
These lower-profile tires are not just a problem for comfort. They are also more susceptible to damage. We once destroyed the low-profile sidewall of a rough-and-ready SUV that the manufacturer advertised blasting through virgin snow in a forest. We destroyed the tire in a parking lot pothole that was nothing special. Just a normal spring road imperfection. And were driving at a walking pace.
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How To Avoid Low Profile Tires
You can't avoid low profile tires altogether, but you can avoid the worst of them. Our suggestion is to try the trim one step down from the top-trim. In many cases, the rim and tire diameter can be one or two inches smaller. That will give you a better ride. In many cases, there are packages that allow you to add back some features to the second from the top trim to come pretty close to the content of the top special trim. Just be sure doing so does not also add in the useless larger diameter tires.
Some ultra-high-performance sports cars make sense with very low profile tires. The tiny differences in handling and braking gained by the super-low profile tires are important to those buyers who imagine themselves on a racetrack. For the rest of us living in reality, these low profile tires add almost nothing to the pleasure of driving cars to work, or even on a lonely country road.
Does your car have low profile tires that are ruining your ride? Tell us in the comments below what you have found.
John Goreham is a life-long car nut and recovering engineer. John's focus areas are technology, safety, and green vehicles. In the 1990s, he was part of a team that built a solar-electric vehicle from scratch. His was the role of battery thermal control designer. For 20 years he applied his engineering and sales talents in the high tech world and published numerous articles in technical journals such as Chemical Processing Magazine. In 2008 he retired from that career and dedicated himself to chasing his dream of being an auto writer. In addition to Torque News, John's work has appeared in print in dozens of American newspapers and he provides reviews to many vehicle shopping sites. You can follow John on Twitter, and view his credentials at Linkedin.
Images by John Goreham. Re-use with permission only.