tauxe@uokvax.UUCP (03/11/86)
Having read the description of the problem(s) and the response I
think that I might be able to add some insight into the problem(s)
1. The grinding into reverse ( the only non-synchromesh gear) is
most probably caused by either a bad clutch pilot bearing or
a warped clutch disc. The drag of a worn pilot bearing keeps
the transmission input shaft spinning at crankshaft speed, thus the
clash going into reverse. A warped clutch disc can do much the same
thing......just enough drag to keep the disc spinning at crank-
shaft speed. By the way, both of these problems can cause the
difficult downshift problem into first that you described.
2. The difficult downshift problem ( in absence of the reverse clash
problem described above) might be caused by the wrong fluid in
the transmission. I purchased a used Volvo which the previous
owner had filled the tranny with 80W gear oil. It had the same
first gear downshift problem that you described. Specs call for
Type F ATF (yes ATF in a manual box) for all weather driving, or
10W-30 if all driving is done at temps over 10 degrees F. I
drained out the gearlube and put in the ATF, and my downshift
problems were cured. So, check the owners manual... Most
mechanics (better known today as repetitive parts swappers)
will blindly fill any manual transmission with 80W gear oil.
Your 15 - 30 minutes driving time might be the clue. In
this time, the 80W fluid is given a chance to heat up and thin a
bit, thus facilitating the downshift. Good Luck.
George W. Tauxe
University of Oklahoma