Tire Sidewall Swelling

A swelling in the flank of the tire indicates that the substructure of the shell has been damaged.

Typical causes for such damage include, for example, driving over curbs at a sharp angle.

Fig 1: Example Of Curb Impact

Courtesy of AUDI OF AMERICA, LLC

Pinching the shell of a tire this way can damage the carcass.

The substructure of the tire is stretched so far that individual fibers in the shell may break.

The extent of the damage depends on the speed of impact, the angle of impact, the air pressure, the axle load and the type of obstacle.

Evidence of pinching on the sidewall of a tire -arrows-

Fig 2: Evidence Of Pinching On Sidewall Of Tire

Courtesy of AUDI OF AMERICA, LLC

NOTE:

Driving over curbs must be avoided!

When it cannot be avoided, curbs should be driven over very slowly at the bluntest possible angle.

Interior view of a tire with a punctured shell.

Fig 3: Identifying Interior View Of A Tire With A Punctured Carcass

Courtesy of AUDI OF AMERICA, LLC

Due to a severe impact, the shell was pinched on the rim flange and is ruptured in the contact area.

Inside tire damage due to impact damage (double rupture)

Fig 4: Identifying Inside Tire Damage Due To Impact Damage (Double Rupture)

Courtesy of AUDI OF AMERICA, LLC

Double rupture -arrows- caused by pinching when driving over a curb. Often not detectable from outside.