Tire Manufacturing — U.S. Industry Rollup Primer

NAICS 2022 code 32621 — Tire Manufacturing. A general-investor guide to the U.S. tire-manufacturing industry as a whole, built by contrasting its two very different halves: making new tires (326211) and retreading worn ones (326212). Written for both public-market and private investors.

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1. Overview

NAICS (North American Industry Classification System) code 32621 is the federal statistical box that holds everything in the United States that counts as making a tire — whether from scratch or by rebuilding a used one. It contains two child industries that share a name but almost nothing else:

• 326211 — Tire Manufacturing (except Retreading): the giant, capital-heavy factories that build brand-new tires for cars, trucks, aircraft and off-road equipment.
• 326212 — Tire Retreading: the far smaller, fragmented network of plants that strip the worn tread off a used commercial-truck tire casing and bond on a fresh one.

For an investor, the single most useful fact about this level is how lopsided it is. New-tire manufacturing is roughly 93% of the revenue but only about 28% of the plants; retreading is about 7% of the revenue but 72% of the plants [1][2]. One half is a handful of billion-dollar factories owned by global multinationals; the other is hundreds of modest regional shops owned by private families and private-equity-backed roll-ups. They are two different businesses — and two different ways to invest — stapled together by a shared product.

What unites them is that a tire is a consumable: it wears out on a schedule and must be replaced whether or not anyone is buying new vehicles. Both halves ultimately ride the same durable base of miles driven. Roughly 85% of tires shipped in the U.S. go into replacement rather than onto new vehicles — in 2025, USTMA reported 285.7 million replacement shipments versus 52.1 million OE shipments [3]. Retreading is simply a cheaper way to serve that same replacement demand in the commercial-truck market.

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2. What's inside — the two child industries and how they differ

This is the heart of the rollup. The two children sit at opposite ends of nearly every axis an investor cares about.

The one-sentence contrast: new-tire manufacturing is a capital-intensive global oligopoly you mostly reach through the stock market (often foreign exchanges); retreading is a fragmented domestic service business you mostly reach through private ownership.

A few of the differences deserve emphasis:

• Scale per plant is ~34× apart. A new-tire factory turns over roughly $165M a year; a retread plant roughly $4.9M [1][2]. A modern greenfield tire plant costs well over $1 billion to build [5]; a retread plant is real capital equipment but an order of magnitude cheaper, which is why one field has ~72 firms and the other ~206 firms [2].
• Concentration runs opposite ways. In new tires the four largest firms make ~64% of output; in retreading the top four make just ~27% [2]. Yet retreading has its own hidden concentration one layer up: three brand systems — Bridgestone's Bandag (~45% of the retreaded truck-tire market), Michelin's Oliver (~24%), and Goodyear (~21%) — control roughly 90% of the retread-technology market, even though the plants themselves are fragmented [6]. So the "public" tire majors quietly sit atop both children.
• Ownership could not be more different. New-tire capacity is held almost entirely by corporations, many foreign-affiliated; there is no cottage segment. Retreading is a private, mid-sized, family-and-PE world — not tiny gig operators, but not public companies either.

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3. How big it is (this level's federal figures)

Our ground-truth federal statistics for NAICS 32621 as a whole:

The HHI (Herfindahl-Hirschman Index) is the standard federal concentration gauge — the sum of each firm's squared market share, where anything under 1,500 is "unconcentrated." At 1,127, the combined level reads as moderately-to-lightly concentrated, but that blended figure hides the split described in §2: the new-tire half is genuinely concentrated (HHI ~1,279) while the retread half is very fragmented (HHI 327) [2].

The figures roll up cleanly — with one telling exception. The children's federal numbers add up almost exactly to the level totals: receipts ($21.06B + $1.62B ≈ $22.68B), employment (52,211 + 6,615 = 58,826) and establishments (128 + 331 = 459) all reconcile [1][2]. But firm counts do not simply add: 72 new-tire firms plus 206 retread firms would be 278, versus ~273 reported at the parent. The gap means a handful of companies operate in both children (a tire major that also owns retread plants) and are counted once at this level — a small but concrete sign of how the two halves overlap at the top.

Undercount caveat. The new-tire half is fully captured — it is a capital-heavy sector of large plants and few firms, with little to hide from federal business statistics. The retread half is materially undercounted, and that pulls down the level total. Federal data count only establishments whose primary business is retreading; a large share of real retread output happens in plants owned by commercial-tire dealers and fleets that are classified under wholesale, retail or repair codes instead [7][8]. Industry cross-checks imply the true retread economy is closer to ~$3 billion than the $1.62B captured here — roughly 15 million tires retreaded annually at typical prices of $150–$400 each [7][8][9]. Two further scope reminders: (1) production is not consumption — the ~$22.7B of domestic output understates what Americans buy, because a large share of new tires sold here are imported (U.S. tire shipments hit a record 337.3 million units in 2024; 2025 came in at 336.3 million) [3]; and (2) the manufacturing core measured by 32621 is far smaller than the ~$28B "U.S. tire industry" figures that bundle in dealers, distribution and suppliers [8].

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4. The investable universe (where value concentrates across the children)

Value at this level is concentrated in the new-tire child (326211) and, within it, in a very small number of names — because ~93% of the revenue lives there and the assets are enormous. The retread child holds most of the plants but little of the public-market value.

U.S.-listed pure-plays (tickers reserved for this section and §10):

Goodyear is the only major full-line tiremaker headquartered and listed in the U.S., and it straddles both children — it makes new tires (326211) and operates roughly 30 retread facilities (UNIRETREAD/Wingfoot) in 326212 [10][12]. It bought Cooper Tire in 2021, consolidating the U.S.-based field to essentially one public champion [10]. Titan is a smaller off-highway specialist that acquired the Carlstar Group (Carlisle-brand specialty tires) in early 2024 [11].

Global majors that run large U.S. plants but list abroad (exposure via foreign exchanges or over-the-counter ADRs — American Depositary Receipts):

The private universe (mostly the retread child). The largest actual retreaders are private commercial-tire dealers, several backed by private equity and actively acquiring. Modern Tire Dealer's 2025 ranking by tread-rubber consumption shows the scale — Southern Tire Mart (Columbia, MS) is the largest, with 28 plants and 9,850 truck retreads per day; Pomp's Tire Service has 25 plants and 4,700 per day; Snider Fleet Solutions, Best-One Tire & Service, and McCarthy Tire Service (70+ service locations and 13 Bandag retread plants across 8 states) round out the top tier [12][16]. New-tire capacity, by contrast, is essentially closed to private buyers — it is held by the multinationals.

Bottom line: direct U.S.-listed exposure is concentrated in Goodyear (broad, and touches both children) and Titan (off-road niche). Everything else is either a foreign equity or — for the retread half — a private-market play.

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5. How the money works

The two children make money in structurally different ways, and understanding the level means holding both models in view.

New-tire manufacturing (326211) — a volume × price/mix minus input-cost business.

• Capacity utilization is everything. Plants carry high fixed costs (curing presses, buildings, labor); owners must run them hot to spread those costs, and under-loaded plants get closed. Goodyear explicitly states that operating income changes disproportionately with sales and that lower production causes under-absorption of factory costs [10].
• Raw materials drive the margin. Roughly half a tire is rubber — synthetic rubber (60–70% of the rubber content, oil-linked) plus natural rubber (a volatile commodity the U.S. imports entirely, bringing in almost $1.5 billion in 2023 from Indonesia, Thailand and Côte d'Ivoire) — with carbon black, steel cord and textiles [17][18]. When rubber and oil rise together, margins compress until makers can raise prices.
• Price and mix are the profit lever. Large-rim (18-inch-plus), performance, all-terrain and EV-specific tires carry materially higher margins than entry-level sizes. During 2025, Goodyear attributed a $443 million worldwide earnings headwind to higher raw materials and a $402 million headwind to conversion costs, partly offset by $465 million of price/mix improvement [10].
• Thin margins. New-tire segment operating margins are historically mid-single-digit, which is why Goodyear's turnaround plan targets lifting margin from ~5% toward ~10%; the Americas segment earned 6.8% in 2025, down from 8.5% in 2024 [10].

Retreading (326212) — a spread-and-throughput business.

• The casing is the value. In a truck tire, most of the manufacturing value is in the steel-belted body (the casing), not the tread. Retreading reuses the casing — often customer-owned, so free to the retreader — and replaces only the cheap part [7]. A new medium- or heavy-duty truck tire requires about 325 pounds of rubber versus about 24 pounds for a retread [19]. A new commercial truck tire runs roughly $300–$800; a retread of the same casing roughly $150–$400 [9], and a good casing can be retreaded two or three times. The trucking industry saves an estimated $3 billion-plus a year using retreads [7][8].
• Throughput and casing yield are the levers. Plants are capital-intensive; unit economics live or die on units-per-day and on how few casings fail inspection. Major retreaders track daily production closely — one operator reported running ~980 units/day before a 2024 slowdown cut it to ~906 [6].
• Two revenue models stacked. The private retreader/dealer earns the retread price on throughput; the brand/system owner (the public tire major) monetizes retreading through a razor-and-blades model — selling tread rubber and equipment and licensing the process to franchisees [6][13].

The common thread: both halves convert steady replacement demand into revenue, and both are thin-margin, throughput-driven operations where keeping the plant full is the whole game.

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6. What drives demand

Both children ultimately ride the same demand engine, with retreading adding a freight-specific overlay:

• Miles driven. Americans drove 3.294 trillion miles in 2024; tread wears with use, creating a steady replacement baseline largely independent of the economy [20]. FHWA's long-term forecast projects average annual VMT growth of only 0.6% through 2053, pointing to a mature replacement market — recurring, but unlikely to grow rapidly from miles alone [21].
• The aging vehicle fleet. The average U.S. light vehicle is about 12.5 years old [22], pushing more owners into the higher-margin replacement channel.
• Electric vehicles (EVs). Heavier and higher-torque, EVs wear tires roughly 20% faster and are replaced perhaps 30% sooner — a volume tailwind for new tires and demand for specialized EV fitments [23].
• Freight and fleet activity (the retread swing factor). Retread demand tracks trucking tonnage; a soft freight market cuts tire wear and defers retreading — precisely what hit the retread child in 2024 [6]. Retreads make up nearly 44% of all commercial truck tires in the U.S. and Canada, showing retreading is mainstream fleet practice [7][8].
• The new-vs-retread price spread. When cheap imported new truck tires are abundant, some fleets buy low-cost "throwaway" tires instead of retreading; when new-tire prices rise (e.g., under tariffs), retreading gains share [6]. USTMA reports 1.1 retreads for every premium new tire sold in the U.S. and Canada, versus fewer than 0.4 for every ultra-low-cost import [8]. This links the two children directly: what helps one can hurt the other.
• Sustainability. A retread uses roughly 7 gallons of oil versus ~22 for a new medium truck tire (a ~68% saving), generates about 70% less manufacturing emissions, and the EPA credits retreading with saving North America 400 million-plus gallons of oil a year [24]. Fleet ESG (environmental, social, governance) targets increasingly favor retreads.

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7. Regulation

Regulation lands differently on the two halves.

New-tire manufacturing is regulated mainly on safety, consumer information and environment:

• NHTSA (National Highway Traffic Safety Administration) sets Federal Motor Vehicle Safety Standards and runs Uniform Tire Quality Grading (treadwear/traction/temperature grades on every passenger sidewall) plus fuel-efficiency labeling. Manufacturers self-certify compliance; NHTSA does not preapprove each product [25][26].
• 6PPD / 6PPD-quinone (the emerging swing factor). 6PPD is an anti-degradant that keeps tires from cracking; its road-runoff breakdown product is acutely toxic to coho salmon. The EPA opened Toxic Substances Control Act rulemaking (advance notice 2024, comments into 2025) and California's DTSC listed 6PPD tires as a "priority product" [27]. The direction and cost of future federal or state requirements are not yet established. A restriction would force reformulation of a core chemistry across the whole industry — a cost and R&D event to watch.
• Air emissions (NESHAP). Stricter rubber-tire NESHAP amendments finalized in November 2024 were revoked under the Congressional Review Act after a resolution was signed in May 2025 and consequently have no legal or enforceable effect [28].
• Trade remedies — antidumping and countervailing duties (e.g., the December 2024 truck-and-bus-tire order on Thailand, rates up to ~48%) are, in practice, among the most consequential rules for domestic economics [29]. In June 2026, the USITC determined that removing the existing passenger and light-truck tire orders on China would likely cause renewed material injury, so those orders remain in place [30].

Retreading carries a lighter federal touch focused on safe use, not a manufacturing standard:

• FMCSA (Federal Motor Carrier Safety Administration) permits retreads on commercial trucks; the one explicit prohibition is retreads on the front (steer) axle of buses [31]. Trucks may run retreads on steer axles subject to load-rating rules, though many fleets voluntarily use new tires on steers as a conservative practice. Vehicles carrying hazardous materials may use retreads (except bus steer wheels) [32].
• No separate NHTSA retread performance standard for truck tires exists [33]. A widely cited 2008 NHTSA-sponsored Commercial Medium Tire Debris Study found road hazards and under-inflation were the leading identifiable causes of tire debris, and no evidence that retread fragments were overrepresented relative to retreads' share of tires in service [34].
• Pending, forward-looking: the bipartisan Retreaded Tire Jobs, Supply Chain Security and Sustainability Act of 2025 (H.R. 3401 / S. 2790) would give fleets a 30% federal tax credit (up to $30/tire) for American-made retreads — a tailwind if enacted [35]. (Not yet law.)

Shared: plant-level EPA (air, wastewater) and OSHA worker-safety rules apply to both.

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8. Consolidation

Consolidation is happening in both children, but in opposite layers.

• New tires — horizontal roll-up of makers. Goodyear's 2021 purchase of Cooper Tire removed the last sizeable independent U.S.-based maker; Titan's 2024 Carlstar deal rolled up specialty off-road brands [10][11]. Scale, brand and distribution are the moats, and the four-firm share sits at ~64% [2]. Rather than exit, foreign majors are building U.S. capacity behind the tariff wall — the industry has pledged $6.5 billion-plus in recent capital projects (Hankook's $1.6B Clarksville, TN expansion; Bridgestone's $550M Tennessee upgrade; Michelin's ~$325M North American commitments) [5]. Plant competitiveness remains a material asset risk — Sumitomo Rubber's decision to end U.S. tire production and serve North America with imports illustrates that a recognized brand and prior capital investment do not guarantee a viable domestic plant [36].
• Retreading — roll-up of the fragmented plant layer. The plants are a field of 331 regional operators, but private-equity-backed dealers (Southern Tire Mart, Snider, Best-One, McCarthy) have been buying up independents and their captive retread plants, drawn by recurring fleet-service revenue and local route density [12][16]. The U.S. plant count has declined dramatically — from more than 3,000 in 1982 to about 500 in 2023 [8]. Meanwhile the manufacturers have pruned captive service networks (Bridgestone dissolved its remaining GCR company-owned locations in 2022) [6].

The net effect across the level: a stable brand oligopoly at the top (the same few multinationals dominate new-tire making and retread technology) sitting over a consolidating but still-fragmented independent middle in retreading.

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9. Risks

Risks common to the whole level:

• Input-cost volatility. Natural rubber, oil-linked synthetic rubber and carbon black can move fast and together, compressing already-thin margins. The U.S. depends entirely on imported natural rubber, concentrated in Southeast Asia [17][18].
• Import undercutting. Low-cost imported new tires cap pricing power in the new-tire replacement market and degrade the long-term casing pool retreaders depend on (throwaway-grade casings often can't survive multiple lives) [6].
• Trade-policy whiplash. Tariffs and antidumping duties are a double-edged sword — they protect U.S. plants and tilt fleets toward retreading, but raise input costs and invite retaliation [6][29]. Goodyear's 2026 outlook forecast an approximately $300 million annualized tariff cost based on then-current rates [10].
• Thin margins & capital intensity. Both children are mid-single-digit-margin, throughput-dependent businesses with expensive, hard-to-close plants.

Risks that differ by child:

• New tires carry more exposure to 6PPD reformulation, EV-driven design change, legacy pension/retiree costs, and the OE (original-equipment) auto-production cycle. Goodyear warns that lower automotive production and lower tire demand can cause under-absorbed fixed costs [10].
• Retreading carries more exposure to the freight cycle (in 2024 more than half of retreaders reported lower revenue), the new-vs-retread price spread, casing-supply erosion, and dependence on a few system owners for tread rubber and franchise terms [6][37].

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10. How to invest & outlook

Public-market routes (concentrated almost entirely in the new-tire child):

• Goodyear (NASDAQ: GT) — the direct, liquid U.S. bet and the one name that touches both children; but it is a turnaround story ("Goodyear Forward" is selling non-core units to cut debt and roughly double segment margin toward ~10%) [10]. Reward hinges on execution and stable rubber prices.
• Titan International (NYSE: TWI) — a smaller-cap off-road/agricultural cyclical, tied to farm and construction equipment more than passenger tires [11].
• Foreign majors — Bridgestone (BRDCY), Michelin (MGDDY), Continental (CTTAY) and others give diversified, often better-margin exposure to new-tire making and the retread-technology oligopoly, via foreign exchanges or OTC ADRs [15][22]. Bridgestone (Bandag) offers the most direct retread-brand leadership, but it is a fraction of a global conglomerate.
• Indirect — broad auto-parts/industrials funds hold these names without single-stock risk.

Because reported profits are thin and rubber-price-sensitive, investors typically watch replacement-tire volumes, price/mix (large-rim share), raw-material costs, and segment operating margin more than headline revenue.

Private routes (mostly the retread child):

• New-tire manufacturing is largely closed to private buyers. The genuine private opportunity is operating ownership of retreading — acquiring or building commercial-tire dealers with captive retread plants, or backing the regional roll-ups already consolidating the space. The attractions are recurring fleet-service revenue, sticky cost-per-mile relationships, local density, and a franchise model (Bandag, Michelin, Goodyear) that lowers the technology barrier; the risks are cyclicality, thin margins and casing-supply erosion [6][12][16]. Diligence should focus on casing ownership and loss rates, rejection and scrap rates, output per labor hour, cure utilization, pickup-and-delivery density, customer concentration, warranty history, franchise terms and environmental/fire compliance. Adjacent fragmented links — tire retail/installation and distribution — offer further private exposure.

Near-term outlook. The demand backdrop for the level is durable: U.S. tire shipments at 336–337 million units, a fleet averaging ~12.5 years, 3.3-trillion-plus miles driven, and EVs that eat tires faster all support a steady replacement base [3][20][22][23]. Expect low-single-digit unit growth in new tires and low-to-mid single-digit growth in retreading (~4.2%/yr forecast through 2029, adding roughly $927 million to the U.S. market) [4]. Profitability at both levels will be set less by volume than by input costs, mix, the freight cycle, and trade policy. For U.S.-listed investors the reality is stark: this is largely a bet on Goodyear's margin turnaround, a niche bet on Titan, or a step offshore to the global majors. For private capital, it is the quieter, more accessible retread half — a slow-growing, defensive, deeply practical business that rewards operators who run their plants full and hold their fleet relationships.

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Sources

1. U.S. Census Bureau, County Business Patterns 2023 (NAICS 32621 and children 326211/326212: employment, establishments, payroll). https://www.census.gov/programs-surveys/cbp.html
2. U.S. Census Bureau, 2022 Economic Census / Annual Business Survey — Industry & Concentration Statistics (NAICS 32621, 326211, 326212: receipts, firms, CR4/CR8/CR20/CR50, HHI). https://www.census.gov/programs-surveys/economic-census.html
3. U.S. Tire Manufacturers Association, USTMA Tire Shipment Forecasts (2024 record 337.3M units; 2025 actual 336.3M; 2026 outlook 338.9M; replacement vs. OE split). https://www.ustires.org/newsroom/ustma-february-2026-forecast
4. Technavio, Tire Retreading Market in US — Growth Analysis, Size and Forecast 2025–2029 (~4.2% CAGR, ~$927M added). https://www.technavio.com/report/tire-retreading-market-in-us-industry-analysis
5. Tire Business / Modern Tire Dealer, Tire Makers Commit $6.5B+ to Capital Projects (Hankook $1.6B Clarksville TN; Bridgestone $550M; Michelin ~$325M). https://www.tirebusiness.com/global-tire-report/tire-makers-commit-more-65b-capital-projects
6. Modern Tire Dealer, Retreading Challenges in 2025: Demand, Tariffs and Costs (three-brand ~90% retread-tech share breakdown, freight cyclicality, price spread, GCR wind-down, daily production tracking). https://www.moderntiredealer.com/commercial-business/article/55275066/retreading-challenges-in-2025-demand-tariffs-and-costs
7. Bandag (Bridgestone), Cost & Savings of Retread Tires (retread pricing, casing economics, $3B+ industry savings). https://commercial.bridgestone.com/en-us/resource-center/articles/retread/retread-cost-savings
8. U.S. Tire Manufacturers Association, Tire Retreading / Retread Report 2024 Addendum (retread undercount, ~44% commercial share, plant count decline 3,000+ to ~500, sustainability figures, ~$28B ecosystem, 1.1 vs. 0.4 retread ratio). https://www.ustires.org/tire-retreading
9. Skyliner Truck Center, Truck Tire Costs in 2026: New, Retread, and Recap Pricing ($300–$800 new, $150–$400 retread). https://www.skylinerrepaircenter.com/blog/truck-tire-costs-in-2026-new-retread-and-recap-pricing/
10. The Goodyear Tire & Rubber Company, 2025 Form 10-K (Americas segment sales, margin, Goodyear Forward plan, Cooper acquisition, raw-material exposure, tariff cost, labor, retread operations). https://www.sec.gov/Archives/edgar/data/42582/000162828026006708/gt-20251231.htm
11. Titan International, Inc., 2025 Form 10-K (off-road tires, Carlstar acquisition, 2025 revenue). https://www.sec.gov/Archives/edgar/data/899751/000089975126000007/twi-20251231.htm
12. Tire Business, Top 50 Commercial Tire Dealers and Retreaders in North America 2024; Modern Tire Dealer, 2025 Top Retreaders (Southern Tire Mart 28 plants/9,850 per day, Pomp's 25 plants/4,700 per day, McCarthy). https://www.tirebusiness.com/news/tire-business-ranks-top-50-commercial-tire-dealers-and-retreaders-north-america-2024
13. Bandag (Bridgestone), The Bandag Difference (200+ North American plants, 2,500+ service points). https://www.bandag.com/en-us/bandag-difference/reliability
14. Tire Retread & Repair Information Bureau (TRIB), Featured Retreaders (Michelin 77 North American retread plants). https://www.retread.org/featured-retreaders
15. Statista, Revenue of the Leading Tire Producers Worldwide 2024. https://www.statista.com/statistics/225677/revenue-of-the-leading-tire-producers-worldwide/
16. McCarthy Tire Service, About Us / Retreading (70+ locations, 13 Bandag plants, 8 states). https://mccarthytire.com/about-mccarthy-tire/
17. IMARC Group / Procurement Resource, Tire Economics & Rubber Price Trends 2024–2025 (raw-material composition, oil-linked input costs). https://www.imarcgroup.com/insight/tire-economics-a-cost-modeling-framework-for-manufacturing-efficiency
18. USDA Climate Hubs, The Potential of Guayule for Commercial Rubber Production in the Southwest (U.S. natural rubber import dependence: ~$1.5B in 2023; Indonesia 47%, Thailand 27%, Côte d'Ivoire 11%). https://www.climatehubs.usda.gov/hubs/southwest/topic/potential-guayule-commercial-rubber-production-southwest
19. NHTSA/EPA, Regulatory Impact Analysis: Medium- and Heavy-Duty Fuel Efficiency (325 lbs rubber for new tire vs. 24 lbs for retread). https://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/Truck_CAFE-GHG_RIA.pdf
20. Federal Highway Administration, Highway Statistics 2024 (VMT: 3.294 trillion in 2024). https://www.fhwa.dot.gov/policyinformation/statistics/2024/vm1.cfm
21. Federal Highway Administration, 2025 VMT Forecast Summary (long-term 0.6% annual growth projection). https://www.fhwa.dot.gov/policyinformation/tables/vmt/vmt_forecast_sum.cfm
22. Mordor Intelligence, United States Tire Market Size, Share & Trends, 2025 (market size, brand shares, fleet age ~12.5 years, plant clusters). https://www.mordorintelligence.com/industry-reports/united-states-tire-market
23. Recharged / Newsweek, EV Tire Wear and Replacement Intervals (EV wear ~20–30% faster), 2024–2025. https://recharged.com/articles/do-ev-tires-wear-faster
24. Tire Retread & Repair Information Bureau (TRIB), Environmental Benefits of Retreading (7 vs. 22 gallons oil, 70% less emissions, 400M+ gallons saved). https://www.retread.org/environmental-benefits-of-retreading
25. Wikipedia, Uniform Tire Quality Grading, and NHTSA TireWise (UTQG, fuel-efficiency labeling). https://en.wikipedia.org/wiki/Uniform_Tire_Quality_Grading
26. NHTSA, Self-Certification of Motor Vehicle Equipment (manufacturers self-certify FMVSS compliance). https://www.nhtsa.gov/interpretations/aiam5168
27. U.S. EPA, Advance Notice of Proposed Rulemaking on 6PPD and 6PPD-quinone (2024–2025); California DTSC Priority Product: Motor Vehicle Tires Containing 6PPD. https://www.epa.gov/newsreleases/epa-issues-advance-notice-proposed-rulemaking-protect-salmon-chemical-used-rubber
28. U.S. EPA, Rubber Tire Manufacturing NESHAP (November 2024 amendments revoked under CRA, May 2025). https://www.epa.gov/stationary-sources-air-pollution/rubber-tire-manufacturing-national-emission-standards-hazardous
29. U.S. Federal Register, Truck and Bus Tires From Thailand: Antidumping Duty Order, 2024. https://www.federalregister.gov/documents/2024/12/17/2024-29606/truck-and-bus-tires-from-thailand-antidumping-duty-order
30. U.S. International Trade Commission, Passenger Vehicle and Light Truck Tires From China: Continuation of Antidumping and Countervailing Duty Orders, June 2026. https://www.usitc.gov/press_room/news_release/2026/er0623_68791.htm
31. 49 CFR 393.75 and My Safety Manager, DOT Tire Regulations: Ultimate Guide (bus steer-axle prohibition). https://www.mysafetymanager.com/dot-tire-regulations/
32. Federal Motor Carrier Safety Administration (FMCSA), May a vehicle transport HM when equipped with retreaded tires? https://www.fmcsa.dot.gov/safety/may-vehicle-transport-hm-when-equipped-retreaded-tires
33. NHTSA, Interpretation Letter GF005203, Retreaded Truck Tires (no federal performance standard for retreaded truck tires). https://www.nhtsa.gov/interpretations/gf005203
34. NHTSA, Commercial Medium Tire Debris Study, DOT HS 811 060, 2008 (road hazards and under-inflation as leading causes). https://www.retread.org/_files/ugd/51429a_a14fe536fe5a40ab8566729817a9d436.pdf
35. Tire Review, USTMA Endorses Legislation H.R.3401 to Enhance U.S. Tire Retreading Industry, 2025 (H.R. 3401 / S. 2790, 30% credit up to $30/tire). https://www.tirereview.com/american-made-retreaded-tires/
36. Sumitomo Rubber Industries, Q3 2024 Financial Report Discussion (U.S. production exit). https://www.srigroup.co.jp/english/ir/library/financial-report/dvql4p000000q84b-att/scripts_2024_q3_en.pdf
37. Fleet Maintenance, Retreaders predict demand fluctuations in 2024. https://www.fleetmaintenance.com/equipment/brakes-tire-and-wheel/article/55028171/retreader-industry-outlook-2024