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Ask a technical question about OTR tyres.

Plain-language answers and independent opinion, with citations from publicly available manufacturer databooks, TRA standards, and 50 years of independent OTR trading. Free to use. Independent of every tyre manufacturer.

Questions are processed by third-party AI providers, some overseas, don't include confidential or personal information. Answers are general reference and the opinion of an independent trader, not engineering advice. This site is maintained by Jewell Tyres, an independent trader, not a tyre engineer or manufacturer; enquiries route to it commercially. Use of the Portal is subject to our Terms and Privacy.

Best tyre for CAT 992K in iron ore What is a TRA E-4 service code? How do I calculate TKPH? 26.5R25 alternatives to Bridgestone Can I mix radial and bias on the same machine?

AI-GENERATED. Answers draw on publicly available manufacturer databooks, TRA standards and AS4457 material, usually with citations. Treat them as the informed opinion of an independent trader, not advice from a tyre engineer, and not a professional recommendation. They can be incomplete, out of date or wrong. Confirm anything safety-critical against current OEM specifications and a competent person before acting.