When is a winter tire too far gone to be repaired and reused safely?

Today’s winter tires are engineered to last, so a puncture doesn’t have to mean replacement. But how do you know when a repair is an option? What steps are involved?

The location, the type, and scope of the damage are the key factors used to determine whether to repair or replace a tire. All tire technicians should look to the USTMA (U.S. Tire Manufacturers Association) for guidance on tire repairs.

“Industry guidelines do not permit repairs to the sidewall or the shoulder area of any tire, including winter tires,” explains Dave Scheklesky, Toyo Tire’s Senior Director of Marketing.

“In terms of size, a puncture on the tread face of 1/4-inch or less, like a nail or screw, may be repaired if there is no internal damage which can be found when the tire is dismounted. Larger punctures or damage such as large, deep cuts or gashes are not repairable, and the tire will have to be replaced, especially if the belts are impacted, which could affect the structural stability and overall strength of the tire.”

Quality repairs

“You want to go to a dealer that has proper training and equipment to perform a good plug and patch,” adds Greg Cressman, Technical Service Director, Yokohama. “You want a combination plug and patch. Other things for the tire technician to look for would be the condition of the tread on the tire. Look for irregular wear or chunking, or any kind of cutting that is happening to the tire.

“We recommend tire technicians look for external signs such as severe scuffing on the sidewalls, which indicate that a tire may have been driven while flat or with very low tire pressure,” adds Scheklesky. “Tire technicians should always remove the tire from the rim and do a thorough internal inspection for any concealed damage that otherwise could go unnoticed. These procedures and inspections will significantly reduce the risk of putting a compromised tire back into service.”

You will also want to look at the DOT to see how old the tire is. “You may be asked to repair an eight-year-old tire, and as a tire repair professional, you would want to think about that pretty close and follow guidelines referring to tire aging,” adds Cressman.

When repairing a tire, keep in mind the following criteria:

• Tires must be removed from the rim/wheel assembly and inspected for all possible damage—including damage to the inner liner.
• Tire repairs cannot overlap with other repairs.
• A rubber stem, or plug, must be applied to fill the puncture injury and a patch must be applied to seal the inner liner (a plug alone is an unacceptable repair).