Just recently, my Saginaw 4-speed starting giving me problems going into reverse. I have a V-Gate shifter with a separate knob for reverse. I literally have to pull the knob backwards as hard as I can to get it to go into reverse. As soon as I let go it's out of reverse. I looked under at the linkage and saw no binding. I always keep it serviced with the correct oil.
I'm not a transmission guy but was hoping somebody here may have seen these symptoms.