silverado 2500 brake pads

I have a 2001 standard duty 2500 Silverado with approx. 125000 miles. It has the origional brake pads, and braking is still great; however I want to do a brake job this year. Were the stock pads in this model semi or ceramic?
Thanks

semi. don't do ceramics, good chance ending with loud rubbing noise when coming to a holt.
why change pads? are they below spec? don't fix it if it ain't brok.