I have a D100 lawn mower that is about 12 years old. It is one with a manual transmissio/transaxle. Over the years, there has been slight seepage around the axle shafts where they go into the transaxle. I would like to check the fluid level and top it off if possible. Talking with my JD dealer about it, he didn’t have a clue where there would be a fill plug or what weight oil to use. I don’t find a fill plug in the parts that are visible. Any help would be appreciated. Thanks. BP