Replacing Rear Differential Fluid

[humanoid]

My mom's got a '93 GS300 and I wanted to change out the rear diff. fluid. Should I stick with Toyota or can I use something like Amsoil? What weight should I use?

[1sikgs]

My mom's got a '93 GS300 and I wanted to change out the rear diff. fluid. Should I stick with Toyota or can I use something like Amsoil? What weight should I use?

use a synthtic gear oil. it makes a big difference. 75w90 or 80w90 is what you should use