I seem to catch something new about every other month, this one being 3 weeks ago but i finally got the chance to upload this one, its pretty entertaining, when else are you gonna see a truck make a lot of sparks?!
http://www.youtube.com/watch?v=8wKzpfY2DdQ
So...what the heck is this?
From a search for, railroad track welding truck
Sure looks the same and they were definitely welding.
No doubt they do some grinding to finish up.
http://www.hollandco.com/equipment/flash-butt-rail-welding-equipment/in-track-welding-equipment/mobile-welders/containerized-welding-system-on-truck
A lot of rail maintenance today is done by companies under contract to the railroad.
Rich