Thank you guys :-) I know well the conversion from Kgm to ftlbs to Nm.
When I removed the axle the first time it came easily, so I suppose it was tightened to only 20 Nm. This value (20 Nm) even if it's low, it's the value I see the most in the manual. I saw the 65 Nm value only once instead. But as you correctly say, it's an M14 thread so it could bare higher torque.
Honestly I don't know but it's my life in this value, if I go wrong I could kill myself.
I'll search in other manuals, but for now I think 20 Nm is the correct one, being in the table at the beginning of the service manual.