I guess if Caterpillar really wants their trade secrets stolen and engineering copied they could go outsource the new Tier IV engine line to a Chinese firm...
CNR have fully built at least 210 16-265H in China, including casting and machining the block
CSR are building the 16 cylinder GEVO (the HXN5 is 6250HP), and exporting GEVO components back to the USA
Building diesel engines is not rocket science, why would you not license to a low wage source, then ship components back to drop your own cost of production?
I believe that the Cat 3500 family is now built in China
The Cummins QSK60 and 78 have a German cast and machined block, with the engines assembled in the UK
MTU (a Rolls Royce/Daimler Benz JV) use the Detroit Diesel trade name in the US, how much of a Detroit Diesel is now US sourced? Or are the engines bolted together in the US from foreign manufactured components?
Modern diesel engines are international
How many bogies under US domestic locomotives are now cast/machined in the USA? I recollect seeing GE's with SCAW bogies. Americast and Atchison are now owned by Australian listed Bradken, with Bradken's foundries now located in China