Watch in 4K! This engineer knows how to work the horn! Amtrak Pacific Surfliner cab car #6905 has the loudest K5LA out of all the other cab cars, hands down. It's also a perfectly tuned K5LA. Now, this will never beat the O.G. sound that the Surfliner cab cars use to have in the early 2000s-2010s, but it sure has a nice ring to it. Well, that ring is more like the hearing damage you will receive from 6905! Enjoy the video!