How do some car companies get away hiding the fact they do not provide five wheels and tires with their vehicles. They may save money by using run flat tires and eliminating the spare, but that means it costs the buyer more because he can't rotate through five wheels and tires for maximum life before replacement time. – Harvey
If you did in fact rotate through five tires, you would have to buy five new ones instead of four, so no advantage there.
An extremely small percentage of vehicle owners rotate through a full set of tires, including the spare when available, so this is, in most cases, a useless appendage at a time when punctured or otherwise damaged tires are less common.
The reasons for run-flats do not include cost savings. They cost more. Manufacturers chose them to save space and weight.
In this age of 17- to 20-inch wheels and tires, the fifth one is heavy and takes up a huge amount of space in the trunk or cargo area. Designers and engineers fight tooth and nail for every centimetre of space and gram of weight. Eliminating the spare is an obvious and easy solution.
In the vast majority of cases, the manufacturer provides years of free roadside assistance so you don't even have to get your hands dirty changing a tire.
But, like you, I am not a fan of run-flat tires, but for different reasons. Because of their rigid sidewalls, they provide a stiffer ride and they commonly come in sizes that are not readily available in winter rubber. There have been significant advances in these tires, including different rubber compounds and more compliant sidewalls, but I still prefer conventional tires – even if I never use the spare.
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