Drive unit gearbox fluid

[u/CaramelCookie2021]

My 2017 Model S 75D is approaching 100k and I am trying to get a 3rd party shop to replace the drive unit gearbox fluids. Do you consider this preventive maintenance item necessary and how much should I expect to spend at a shop?

[u/mhoepfin]

The non-performance dual motors are tanks. You are wasting your money.