i have an 84 that until about 2 weeks ago shifted like butter. now, even with the pedal all the way to the floor it is nearly impossible to get from one gear to the next without really battling with it (meaning it takes all my strength to pull/push the shift lever into the next gear). putting it into reverse grinds like crazy. what interests me most is that when the car is off and the clutch is depressed, it shifts just fine into all gears.
is there some adjustment or fluid that i need to make sure it has? please be gentle with me since i really know virtually nothing about cars and am trying to learn as much as possible. i have the manuals (chiltons, haynes, and a tune/modify one by motorbooks) that i have searched through, but i really dont know what to look for. any help or advice is greatly appreciated.

If it has started doing this all on its own, i.e. no work done to it, then the pilot bearing / bushing has probably started having friction with the tip of the clutch gear.

Usually by the time that happens, the clutch is pretty much at the end of its service life anyway.

I'd suggest just putting a new clutch in it. Don't forget a new pilot.

ok about 5 minutes after posting this i got to thinking about the fluid levels and ent out and checked everything...one of them was empty, i put some brake fluid in it and VOILA! clutch is shifting beautifully again! omg i was so so worried about this since it is my daily driver.

thank you SO much for your advice. i am going to take it into the repair shop and make sure the clutch hasnt been damaged.

Well, sometimes the simple things are the most easily overlooked....

It wouldn't have damaged the clutch, mostly the transmission. That puts A BUNCH of extra wear on the synchros.

But now, the $64,000 question: What happened to the fluid? Those things don't generally leak AT ALL; like, hundreds of thousands of miles without needing fluid. Not a good sign.