R180 Side axle orientation

[Riceburner]

In the photo you’ll see a ‘flat’ on the axle shaft. Does this mean the axle flat should be facing a particular direction in the diff centre?

 

The axle will go in anyway you want it providing the splines are aligned. Wondering if the flat is an oil feed or something.

[HKSZ]

Always wondered this myself,

so I align it up with the pin hole oiler in the diff carrier?

[Riceburner]

I couldn’t find any reference to it in the Yellow Nissan service manual.

 

The Torsen  just has two crossing groves in the side of the carrier, kind of like an ‘X’. Not sure what the OS Giken has yet.

[Retro Z]

In trade school I was told that it's for the bearing to vent off heat and not for oiling. Could be wrong.

[Riceburner]

Picture shows OS Giken with bearing fitted. The order from inside to outside is bearing with rollers, inner bearing race, Diff centre bearing hub. So the bearing doesn’t have direct contact with the axle.

The smooth inside of the OS Centre hub has no holes or grooves and that’s where the flat from the side axle will sit. 

Perhaps is an oil relief path from the diff centre, either way with the Giken centre it doesn’t seem to matter which way the flat is facing does it?

 

 

[KatoKid]

I would say its just a path way for lubrication G man