crawl under and look at the linkage and bellhousing, if it's all covered in mud then hose it off.
There shouldn't be mud inside the bell housing where the clutch is.
"But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." - Thomas Jefferson, Notes on the State of Virginia, 1782
Arguing with a truck driver is like wrestling with a pig in mud, eventually you realize the pig enjoys it.