Whitewall tire

Whitewall tires or white sidewall (WSW) tires are tires having a stripe or entire sidewall of white rubber. These tires were most commonly used from the early 1900s to around the mid 1970s.

The use of whitewall rubber for wheels has been traced to a small tire company in Chicago called Vogue Tyre and Rubber Co that made them for their horse and chauffeur drawn carriages in 1914.

Early automobile tires were made of pure natural rubber with various chemicals mixed into the tread compounds to make them wear better. The best of these was zinc oxide, a pure white substance that increased traction and also made the entire tire white. However, the white rubber did not offer sufficient endurance, so carbon black was added to the rubber to greatly increase tread life. Using carbon black only in the tread produced tires with inner and outer sidewalls of white rubber. Later, entirely black tires became available, the still extant white sidewalls being covered with a somewhat thin, black colored layer of rubber. Should a black sidewall tire have been severely scuffed against a curb, the underlying white rubber would be revealed; it is in a similar manner that raised white letter (RWL) tires are made.

The status of whitewall tires versus blackwall tires was originally the reverse of what it later became, with fully black tires requiring a greater amount of carbon black and less effort to maintain a clean appearance these were considered the premium tire; since the black tires first became available they were commonly fitted to many luxury cars through the 1930s. During the late-1920s gleaming whitewalls contrasted against darker surroundings were considered a stylish, but high-maintenance feature. The popularity of whitewalls as an option increased during the 1930s. On April 6, 1934, Ford introduced whitewall tires as an $11.25 option on all its new cars. Automobile designs incorporating streamlining eventually rendered the two-sided whitewall obsolete.

The availability of whitewall tires was limited in the U.S. during the supply shortages of raw materials during World War II and the Korean War.

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