Glossary

Innerliner

Last reviewed: 2026-05-20

The innermost layer of a tubeless tire — a specialized rubber compound that functions as the air barrier, replacing the inner tube used in older bias-ply tires. Damage to the innerliner from running flat or from improper repair techniques can cause slow air loss even without a visible external defect.

A tire that holds pressure initially after a puncture repair but loses air slowly may have innerliner damage that the repair did not seal completely.

Real-World Use

After a puncture repair, a tire passes a water-submersion test but shows slow pressure loss — the innerliner has a crack adjacent to the repair that is allowing air to migrate through the casing.

What to Pair It With

Read this term with the full tire sidewall, vehicle rating information, manufacturer documentation, and the actual condition of the tire.

This site is for general information only. It does not replace professional tire service, DOT compliance advice, tire manufacturer instructions, vehicle manufacturer recommendations, or fleet policy.