Home / Blog / DOT Certification for an In-House Retread Line

IN-HOUSE RETREADING

DOT Certification for an In-House Retread Line: What FMVSS 117 Actually Requires

Equipment and space get most of the attention when a fleet plans its own retread shop. The part that's easy to miss: the moment you retread a tire, you become a retreader of record under federal law — with your own obligations to NHTSA.

Published September 11, 2026 · Good Hope Retreaders

Our guides on the cost to set up a retread shop and the economics of running your own line cover the machinery and the math. There's a third piece that a fleet weighing in-house retreading needs to plan for early, because it isn't optional and it isn't fast: in the United States, retreading a tire for use on public roads makes you a "retreader" under federal law, and that status comes with its own certification, marking, and recordkeeping duties — separate from anything the fleet already does as a motor carrier.

None of this is a reason not to go in-house. It's a known, finite checklist — but it has to be on the timeline next to the equipment order, not discovered after the first cured tire comes out of the chamber.

The rule that applies: FMVSS No. 117

Federal Motor Vehicle Safety Standard No. 117, codified at 49 CFR 571.117, sets performance requirements for retreaded pneumatic tires sold or introduced into commerce in the US — things like high-speed performance and physical construction. Section 6.1 of the standard requires the retreader to affix its own DOT symbol to the tire, certifying that the tire, as retreaded, meets all of Standard 117's requirements. That certification is the retreader's, not the original tire manufacturer's — the moment a casing goes through your line, your shop is the one making that claim to the federal government.

Getting a plant code, and what it does

The identification and recordkeeping rules sit in 49 CFR Part 574. Under 574.5(b)(1), every tire a retreader processes has to carry a Tire Identification Number (TIN) — molded, branded, or laser-etched into the sidewall — and the first three symbols of that TIN are a plant code unique to your shop. You don't choose that code yourself: 574.6 requires applying in writing to NHTSA's Office of Vehicle Safety Compliance, and a separate code is assigned to each plant location, so a fleet running more than one retread shop needs a code per site, not per company.

For a retreaded tire specifically, the TIN structure is its own format, not a copy of the new-tire TIN: three symbols for the retreader's plant code, two more identifying the retread mold or matrix used (or a size code if no matrix applies), and up to four optional symbols describing the tire, plus a date code. Only a fixed set of alphanumeric characters is permitted in any of these fields — the regulation spells out exactly which letters and digits are allowed.

Recordkeeping is part of the deal, not a formality

Part 574's title is "Tire Identification and Recordkeeping" for a reason. The TIN system exists so that if a retreaded tire is ever the subject of a recall or a safety investigation, NHTSA and the retreader can trace it back to the specific plant, matrix, and production run. That means a fleet running its own line needs to actually keep the records tied to its plant code and TINs — which casings went through which cure cycle, on which date — not just mold tires with a compliant-looking number and move on. This is the same traceability discipline that already matters for casing quality control; our casing inspection guide and casing ownership piece cover why tracking a casing's history pays off well beyond the certification requirement.

What this means for the timeline

The practical implication is sequencing. A plant code application to NHTSA, mold or matrix selection that determines your TIN's middle two symbols, and the sidewall marking method (molded, branded, or laser-etched within 24 hours of the tire leaving the mold, per 574.5) all need to be settled before your line runs its first commercial-use retread — not after. Building this into the same planning pass as your equipment and facility budget avoids a gap between "the chamber is running" and "we're legally allowed to put this tire on a truck."

Canadian fleets should note this is specifically a US federal framework administered by NHTSA; Canada's retread requirements run through different standards and provincial rules (our guide to steer-axle rules covers where Canadian and US requirements diverge). A fleet operating on both sides of the border needs to confirm which regime applies to tires used in each jurisdiction — this isn't a case where one certification automatically covers both.

The bottom line

None of this is a reason to stay locked into an outside branded retreader if the economics and volume favour running your own line — thousands of independent retread shops across North America operate under exactly this framework today. It's simply a real, fixed part of "what it actually takes" that belongs on the same checklist as the buffer, the builder, and the curing chamber: apply for your plant code early, decide your marking method and matrix numbering before you cut your first casing, and build the recordkeeping habit in from day one rather than retrofitting it later.

Planning your own certified line?

We supply the machinery, tooling, and consumables for an in-house retread line with transparent all-in Canadian pricing and delivery from our Ontario warehouse — manufacturer-direct, no distributor markup. Tell us your volume and tire sizes and we'll help you spec a line that fits your shop.

Get an equipment quote →