It didn’t. They use illegal aliens to carry it over the border, then load it up on trucks stolen in the Phoenix or Tucson area.
Here in Texas, the drug runners steal 3/4 and 1 ton trucks because of their carrying capacity and their beefed up suspensions. This allows them to carry more pot and drive across fields without tearing up the undercarriage. Buddy of mine in Houston had a nice 1 ton 4X4 crew cab diesel. Stolen out of a resturant parking lot while he was eating dinner. Truck was found outside of McAllen Texas with a couple of flats. Guess they blew the tires out and abandonded the truck.