Some signs of transmission problems are the transmission refusing to go into gear, the smell of burning transmission fluid and noises coming from the transmission when the car is in neutral. Other signs are gears slipping, a dragging clutch and leaking transmission fluid.
The transmission may refuse to go into gear on attempts to put the car into first gear after stopping. This problem can be caused by low transmission fluid, wrong fluid viscosity or required adjustment of the shift cables or clutch linkage.
Noises coming from the transmission when the vehicle is in neutral can include bumping, wheezing, grinding, clunking or humming. These noises may happen infrequently at first and steadily build in frequency and intensity over time as the problem grows worse.