I have a 91 Toyota PU, 4 wheel drive, manual transmission with 143,000 miles. Occasionally, I would have difficulty in shifting to first gear and also when I shift to reverse there is a momentary grind, which sometimes goes away by pressing on the clutch in two succession. I have checked the master and slave cylinder and there are no leaks. I changed the transmission gear oil as well as the differential oil. I also note that there is a slight freeplay on the clutch. I have not had the clutch replaced since I bought the truck in 1991. Does anyone have any idea what could be the problem. I dare to guess that the clutch plates are worn out. Also, how much do those jobs cost in general? Thank you.