[toyomoho]

How many miles? There has been a lot of discussion on TN about changing auto trans fluid. Flush, pan oil change, high mileage trans and flushing, etc. Might do a TN history search.

Suggest dropping and cleaning the pan and magnets (if so equipped). The filter is screen type and can be washed if necessary. Find out if the trans pan has a gasket or uses just sealant.

Draining the pan gets about 1/3 of the fluid, the rest is in the torque converter. As stated by others, repeated changing can clean up the fluid.

If the dipstick states Dexron, Type III is good enough. Have not seen Type 6 in stores. Don't use T4 if the trans specifies Dexron.