Trailer tires should be chosen for the trailer’s approved requirements, not by copying a passenger-car size that seems close. The supplied VEVR catalog identifies ZT301 as a special trailer radial tire pattern. Understanding that designation is an important first step before asking for a quote.
What does ST mean on a tire?
ST stands for Special Trailer. It identifies tires intended for trailer applications rather than general passenger-car service. An ST tire should not be selected as a passenger-car replacement merely because the rim diameter or nominal width matches.
Trailer fitment still requires the correct size, load capability, speed designation, wheel compatibility and operating guidance. Start with the trailer manufacturer’s placard and documentation. If the existing tires differ from that information, have a qualified professional investigate instead of assuming the installed tire is the approved choice.
Examples from the ZT301 catalog
The VEVR ZT301 page lists the source size options, including ST175/80R13 6PR, ST205/75R14 in 6PR and 8PR entries, ST225/75R15 in 8PR and 10PR entries, and ST235/80R16 10PR. These examples show why the complete designation matters when comparing quotations.
Ply rating is a strength/load designation, not a literal count of physical plies, and it should not be used on its own to approve a load. The actual service description and confirmed technical data must be checked. Catalog inclusion does not establish stock, market approval or suitability for a particular trailer.
Five details to confirm before ordering
- The exact tire size specified for the trailer.
- The required service description and confirmed load capability for the installation.
- The compatible wheel dimensions and ratings.
- The intended route, operating conditions and applicable local requirements.
- The exact brand, pattern, quantity and documentation included in the quotation.
Do not infer interchangeability between ST, LT and passenger tires from matching dimensions. Any departure from the original equipment specification should be assessed by an appropriately qualified professional and the relevant manufacturer.
Use confirmed guidance after fitting
Follow the trailer manufacturer’s inflation and loading guidance, and inspect tires for damage, unusual wear and other signs that require professional attention. A tire’s maximum sidewall pressure is not a universal instruction for every trailer. Avoid overloading and make sure the wheel and tire requirements are compatible.
The website provides source-page references to make the catalog traceable, but it is not a fitment approval or a live inventory feed. Read our tire-size guide, review the complete VEVR catalog and contact CAMPINTAL with the full trailer specification. Ask for written confirmation of the proposed ZT301 size before accepting an order.
Sources & editorial note
Product examples are drawn from the supplied CAMPINTAL tire catalog (PDF) and the VEVR pattern pages. Factory descriptions refer only to the visible supplied imagery. General tire guidance is educational and does not replace the vehicle or trailer manufacturer’s instructions or professional fitment advice.
No independent product testing, certification or inventory verification is claimed. Request a confirmed specification for the exact tire before purchase. Contact the team about product details or corrections.
Have a specific tire requirement?
Send the full size, application, quantity and destination market. We will help you identify the product details to confirm.
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