The manual transmission oil was changed using 1.5L of Honda's MTF,[p/n 08798-9031] recommended in all Honda manual transmissions. Change is recommended in "normal conditions" every 90,000 mi / 144,000 km or 6 years, Under "severe conditions" such as Canada geographically or under differing driving patterns, change is recommended every 30,000 mi / 48,000 km or 2 years. Alternatives to the factory recommended fluid exist, including Castrol VMZ80, Amsoil ATF, and Redline MTL. To perform the task: After removing the left side plastic underpan with a 10mm socket, tools required for the change are a 17mm box end wrench to open the fill hole on the left side of the lower part of the transmission seen above, [and possibly a rubber mallet to tap on the wrench, open the inspection/fill hole first]; a 3.8" drive to insert into the square hole in the drain plug; a oil catching container; a funnel with a long extension if filling from the tops, or an oil pump if filling beneath the car. I found it easy to use a two piece funnel that had a fine mesh screen where the extension screws into the bottom of the funnel. I poured the first bottle straight into the funnel, then opened the second container and poured the remainder required into the first, where the volume could be made precise for pouring via the indications on the side of the Honda MTF container. The torque values to tighten the plugs are specified above, as are the Honda MTF specificationsl ; new sealing washers for the plugs are recommended. The vehicle seemed to shift smoother with the fresh new fluid as expected. Please recycle your used oil and transmission fluids. Shine a flash light at the stream of fluid draining to try and spot any metal particles and start with a clean drain to assess what's there more clearly.