clutch problems/questions (long explaination)

[Blue_71]

a little history:

about 2 months ago, i went to turn in my driveway, so i pushed in the clutch to downshift. while holding down the clutch, i went from third to nuetral, and before i got into 2nd, something popped loudly. i could not get it into any gear, and the clutch pedal was stuck to the floor. so, leaving it in nuetral i rolled it down the hill into my neighbors drive. after a quick inspection, i found the ball stud where the z-bar attaches to the frame busted off at the threads. i replaced the ball stud with a beefier version off a 74 C10

what im running:

1971 K20 w/ SM465 and NP205
1998 350, 90 model flywheel (externally balanced ive been told, and made to work with the 1 pc rear seal)
diaghpram 12" towing clutch
stock z-bar, modified to work with angled back ram horns or headers (used to have headers on this truck)

the problem:

after replacing the ball stud, the clutch pedal has been overwhemingly stiff. im used to towing clutches, and this thing has one heck of a hard pedal. also every couple weeks (almost 2.5 excactly) i have to readjust the clutch, because it disengages lower and lower to the floor, to the point of not disengaging anymore. i do have locknuts on each side of the "stud" on the bottem rod, so i know its not moving. ive even marked it with paint to be sure. nothing is moving in the linkage system anywhere. the truck has always jerked hard when letting off the clutch pedal, like the clutch grabs quick

withen the last week however, the clutch has went from hard to soft intermittenly, and sometimes it will not disengage unless i "pump" the pedal once or twice, almost like a bad master or slave cylinder on a hydraulic setup. however, wednesday night a new symptom started. on my way home from work the truck started bucking and shaking all over when i let out on the clutch normally, from a dead stop. i didnt think much about it, but it keeps getting increasingly worse. by thursday night it was so bad it wouldnt even hardly take off, like the clutch is grabbing and letting go quickly. the only way i can get it to take off is to rev the truck up to 2500 or so and dump the clutch which of course results in spinning tires and lots of evil looks.
ive also noticed a strange rattling sound anytime the truck is rolling, weither or not the clutch pedal is pushed in. the sound is not present while sitting still

anyone (still here after reading that book) have any ideas what could be wrong? my initial thought was uncompatable parts between the old manual linkage setup, and the late model engine and flywheel. im begining to wonder if i didnt loose a spring in the clutch disc when it popped and broke the ball stud

also, what is the difference in a borg & beck, and diagphram clutch? im considering going back to the borg & beck 3 finger style like the truck had originally

[Huck]

Josh, sounds like the clutch pressure plate and spring assembly is turning to crap. You need to pull it all and go through it. I would go new.
My 1/2 ton blazer has such a nice soft and smooth clutch, pedal is real easy and it pulls like a tank. Any changing in engagement means you have warn or failing parts.

[msgross]

I was thinking either a throwout bearing or pressure plate. Advance Auto had an 11" for my 68 for $139 (pressure plate, clutch disk, bearing, and the brass part for the crank (name not coming to me right now!))

[jamie72]

thinking of pilot bearing mike?? lol i put the whole advanced auto setup in my blazer years ago, do that and be over it..