Citroen Xsara Picasso 1.6 hdi - stiff gearchange - alangoz

hello ,i have a problem with my gearchange ,it feels like im stirring treacle when i change gear ,this problem comes & goes ...any advice to the cause ??thanks

Citroen Xsara Picasso 1.6 hdi - stiff gearchange - Peter D

Is the gearbox OK when the engine is off. This could be a clutch problem. Regards Peter