Mexico’s growing fleet of Chinese-made heavy trucks is becoming a new obstacle in its quest for relief from U.S. tariffs, as Washington presses for assurances that its southern neighbor isn’t becoming a backdoor for Chinese manufacturers to enter North America.

The value of Mexican imports of Chinese trucks ballooned more than sevenfold in a six-year span, raising concerns among local manufacturers and U.S. authorities, according to two people with knowledge of the matter. The number of Chinese truck companies operating in Mexico has also surged to about 23, creating fresh tension as Mexican negotiators seek relief from U.S. barriers that have weighed on one of the country’s most integrated export industries.

The dispute cuts to the heart of the U.S.-Mexico-Canada Agreement review as to whether Mexico can convince Washington that it’s aligned with the U.S. against China while protecting its own manufacturers from cheap imports and preserving access to its largest market.

Mexican truck manufacturers are asking for a two-sided solution: higher domestic tariffs on Chinese vehicles and a U.S. approach that treats Mexican-made trucks as part of the North American industrial base, not as a threat to it.

The issue is expected to feature in a third round of bilateral talks between Mexico and the U.S. starting Tuesday in Mexico City. The U.S. has said the trade pact won’t be renewed in its current form, though it remains in force while the three countries keep negotiating over disputes including automobiles, steel, supply chains and China’s role in North America.

Mexico’s Economy Ministry, in charge of USMCA negotiations, declined to comment.

American negotiators are increasingly concerned that Chinese vehicles and parts are entering Mexico and could eventually benefit from North American supply chains, according to people familiar with the matter, who asked not to be identified discussing private talks. Those concerns are complicating Mexico’s effort to win relief from U.S. tariffs on medium- and heavy-duty trucks and parts.

Issues to be discussed during the talks, which will be attended by U.S. Trade Representative Jamieson Greer, will include “steel and aluminum and derivative products, automobiles, economic security, labor, agriculture and electronic payment services,” Greer’s office said in a statement on Friday.

Washington imposed 25% tariffs on medium- and heavy-duty trucks and parts in November 2025, though USMCA-qualifying vehicles may have the levy applied only to the value of non-U.S. content, according to USTR’s 2026 autos report.

Mexico’s heavy-vehicle industry is under pressure. Output fell 13% year on year in the first half of 2026, while foreign shipments declined 14.5%, official data show. The U.S. absorbed 92.3% of those sales, highlighting the sector’s vulnerability to shifts in American trade policy.

At home, manufacturers say Chinese rivals are undercutting them with low-cost vehicles while reporting remains opaque.

Mexico’s bus and truck manufacturers are seeking duties of as much as 50% on heavy vehicles from countries that don’t have free-trade agreements with Mexico, mainly China. Existing tariffs for heavy trucks range from 5% to 20%.

The manufacturers have argued that some Chinese units enter Mexico at declared customs values far below market prices, distorting competition and making locally produced trucks less attractive.

Chinese manufacturers and brands with documented heavy-truck or bus activity in Mexico include Yutong Bus Co., BYD Co. and FAW.

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