is it 40% of the invoice?
or 40% of the invoice and shipping cost?
Any “ad valorem” taxes are calculated on cif…….cost, insurance and freight.
If the new car part is made in the US….it could enter under a reduced duty tax regimen (DRCafta) based on the category the part falls into.
Note that if it is a US part, it must qualify as made in the US, not just shipped from the US.
Depending on size, type of part and whether the need is immediate, you may want to consider shipping via a mudanza. This shipping method might avoid being taxed depending on the shipper and the relations they have at Aduana.
Respectfully,
Playacaribe2