On the side of the differential, there is a check plug for the fluid.
First, park the vehicle on a flat surface. Then you can remove the plug. The fluid level should be just below the opening of the plug. Toyota calls for it to be 0.5mm below the opening.
Anything below that is considered to be low fluid level.
This vehicle uses 85W-90 gear oil.
As for the leak, it will depend on where the leak is coming from. It could be the gasket that is on the differential cover. Or it could be from the seal.
Here is a helpful guide:
I have attached diagrams for your reference.
Please let me know if you have any questions.
Images (Click to enlarge)
Saturday, February 5th, 2022 AT 10:43 PM