Note: To remove the drain and filler plugs you will need a hex key or a suitable replacement (see text).
1. Place a suitable container under the transmission drain plug on the bottom of the housing, then remove the plug. To help drain the oil, remove the filler/inspection plug located on the right side of the transmission. You will need an Allen key to remove the plug, but if you don't have one, you can use a tall nut or Allen key and a wrench (see Fig. 2.1, a, b).
Fig. 2.1, a. Using a high nut and wrench to unscrew the gearbox filler plug
Fig. 2.1, b. Location of the gearbox drain plug
2. When all the oil has been drained, tighten the hole plug, installing a new gasket.
3. Fill the gearbox with oil until the oil starts to flow out of the filler hole. The level should be at the bottom edge of the filler hole.
4. When the level is correct, install the plug and tighten it securely.