was trying to add AutoRX to my gearbox, but when i opened the filler hole, a lot of fluid leaked out. so thinking that i lost quite a bit of transmission fluid, i opened the drain plug and everything came out!
so i bought myself 2 quarts of Redline MT-90 (75W90) gear oil and it's GRRRREAT! shifting feels much better now and doesn't feel as hard to engage gears. Especially reverse, there is far less crunching noise now.