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You can remove the drain plug on the pan to drain the fluid. Then to fill it there are two ways but both involve removing the center of the drain plug which is actually the level plug. There is a special tool that is inserted in place where you can pump fluid through it or you can remove the 8mm allen/hex plug on the tail housing and fill it through there. Then start the engine go through each gear and warm the transmission fluid to 80-100 degrees. Once it flows out the center drain plug it is full. You need to do this either on a level surface or lift.
By removing the plug on the tail housing, do I need that special tool to refill or will a simple funnel be effective as well?