Sqeaky steering wheel

Firstly i will say that the car drives fine and is not affected by the problem and the steering wheel is secure. However quite often but not all the time a squeaking rubbing noise comes from behind the steering wheel when turned. This is more frequent when doing full lock slow manouvoures. I am open to ideas. The only thing i have tried is taking the cowling off to have a look but couldn`t see anything wrong but i`m not very experienced with cars. Kind regards Peteshaw