From stop when I put first or second gear I hear a grinding noise. I adjust the cable but that was not the problem. Pedal now is pretty tight, overtight I better say but I saw no improvement. Do you think a low level fluid might cause this? Otherwise no other noises or symptoms except oil leaking up until this.

Thomas

Is the grinding coming from the transmission or is it possibly coming from your flexible joints? Take a look under the car. If you have silver wear marks the joints are sraping on the frame.

No the noise comes from the gears while trying to put 1st gear or any gear, is like trying to put a gear without pressed the clutch fully in.

I just added about 140ml of transmission fluid and things got better, not sure yet but I think problem almost gone! I'll have to do more kilometres to be sure.

Being that neither the 500 OR the 126 have synchro on 1st gear, I would NOT advise anybody to select 1st gear unless the car is stationary. At traffic lights/junctions I often slip the gear-box into 2nd and then into 1st--this helps to line everything up in the gear-box. With regard to graunching when selecting 2nd, if you have a 126 'box I would think that the synchro is worn--if it is a 500 'box, try being slower and more positive with your double-de-clutching.