8014 slew motor oil?

[Webs29]

Hi all, I have a query regarding the slew motor in my 1998 801.4. My machines ID number is 0722315 and machines from M721137 use gear oil to lubricate the slew motor. Looking at the motor I can't seem to find any drain or filler plug. Here is a pic form the service manual about slew gearbox lubrication:



Can anyone give some guidance on this? I assume the oil can be changed or is it a sealed unit for life?
Thanks

[agrimax]

Picture of the slew box for your serial no.
No.6 top left will be the fill and level plug and no.19(magnetic) or no.6 on the right will be the drain.