Lots of people don't realize the emission system on modern diesels absolutely destroys their dependability. Where an older engine could go 1/2 a million miles with just basic maintenance, these newer systems (def, dpf, egr, and so forth) break down often. Some people are reporting multiple failures after 20k miles. This is further exacerbated by the fact that parts for those emission systems are back ordered now due to the very same supply chain problems they created. This is one of the reasons Caterpillar, which used to make some of the most dependable engines, completely exited the commercial trucking market. The solution is going to end up being to use ports in mexico. This will be a huge bonus to the cartels which already control the ports.