Sources & citations

Every number on this site traces back to one of the authoritative sources below. We do not republish data from informational competitors; everything is derived from primary standards, government safety databases, or manufacturer-published documentation.

Standards bodies

• ETRTO 2024 Standards Manual — European Tyre and Rim Technical Organisation. Section width, aspect ratio, overall-diameter formula, load-index tables.
• Tire & Rim Association 2025 Yearbook — North American passenger-tire standards reference. Load index to maximum-load conversion, speed-rating ladder.
• ISO 4000-1:2021 — Passenger car tyres and rims, Part 1: tyre designations.
• SAE International — J1349 (speedometer accuracy), J2452 (rolling resistance), various SAE technical papers we cite per-page.
• Tire Industry Association — TIA technical bulletins on plus-sizing, mounting, and TPMS service.

Government safety databases

• NHTSA — Federal Motor Vehicle Safety Standards (FMVSS 101, 135, 138), UTQG treadwear / traction / temperature ratings database, recall records, SaferCar VPIC.
• UNECE — Regulation 30 (passenger tyres), Regulation 39 (speedometer accuracy).
• EU tire-label database — energy efficiency class, wet grip, exterior rolling noise per Regulation 2020/740.
• UK DVSA, Transport Canada, Australian Department of Infrastructure (ADR) — region-specific regulatory references.

Manufacturer documentation

Approved fitment ranges, warranty mileage, OEM tire markings, TPMS reset procedures, and wheel-package option codes are sourced directly from manufacturer-published owner's manuals, service bulletins (TSBs), and accessory catalogs. We cite the specific document on every page where that data appears.

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Corrections

If a number on this site disagrees with what you find on the authoritative source, email [email protected] with the page URL and the source reference. Verified corrections are applied within one business day.