EU limit for sulphur in diesel is 10 mg/kg (10 PPM) US limit is 15 PPM.CP4’s are not trash..but the are made for high sulfur European diesel..we have LOW SULFUR DIESEL in the United States..the lubricity isn’t there for the CP4 gears
May be different additives used between EU and US diesel though, know some nasty is added over here to counteract the bio.