The tariffs that Trump had threatened to impose on Mexico starting June 10th will not be going on to effect. Trump tweeted out that Mexico had made concessions to deploy their newly formed Nation Guard to their own southern border and that it only took two days for Mexico to bend to Trump's demands. This is false.
The truth, according to a report in the New York Times is that Mexico had already agreed to do that back in March 2019 during secret talks between the (at the time) Director of Homeland Security Kirstjen Nielsen and the Mexican Secretary of Interior Olga Sanchez. Further, Trump claimed a victory via his tariff efforts saying that he had reached an agreement that Mexico would hold more asylum-seekers on the Mexican side of the border while the U.S. processes their cases. The timing of this is also false. The agreement was already reached at the same meeting in March. Where Trump failed was in getting Mexico to accept a "Safe Third Country" treaty that would have given the U.S. the ability to reject asylum seekers if they had not first sought asylum in Mexico.
In opposition to the tariffs was many Senators from Trump's own party, including the Senate Majority Leader Mitch McConnell who said, "There is not much support in my conference for tariffs, that's for sure". Many in the GOP were whispering that the Senate was going to pass a resolution disapproving of the tariffs, causing embarrassment for Trump and making him look weak. Most likely that whispering got to Trump himself and so then he laid claim to the previously agreed "concessions" from Mexico in order to save face and drop the tariff while claiming victory.
Many business leaders too were calling for relief from the tariffs, the auto industry would have been hit especially hard with a significant number of components passing over the border multiple times.
Below is a list of vehicles that are currently assembled in Mexico for U.S. consumption:
Chevrolet Silverado 1500 Crew Cab
Ford Transit Connect
GMC Sierra 1500 Crew Cab
GMC Terrain (certain models)
Nissan Frontier (certain models)
Nissan Versa Note
Nissan NV200 Cargo
Ram 1500 Regular Cab
Volkswagen Golf SportWagen