The importance of using the correct fasteners in all areas of the machine can never be overstated. This M14 Flange Nut is no exception and is specific to this application in the axle assembly.
Threads will be accurate, they will be hardened and tempered correctly with the correct plated finish. In short, it would be unwise, to say the least, to use anything other than genuine factory supplied fasteners.
Please make sure part numbers ordered are compatible with your model. Use the correct specification fasteners, why take the chance with any other type?