Nissan Repair: 1999 Nissan Altima - Manual 5 SPD, clutch slave cylinder, manual transaxle

Question
Driving my 1999 Nissan Altima 2.4L Manual/5 SPD yesturday a Knock began close to my feet. I feel it in all pedals and the stick shift slightly. When the clutch is engaged and the car is slowing down the knock get's real loud as if a hammer is pong/banging on something metal. After parking it I opened the hood and cannot find anything leaking from above. Getting under it I find a somewhat clear oil (Not engine oil because that's black and needs to be replaced. It was dripping off I believe it's called the bell housing? Not sure but its the part that's connected to the right side of the engine if looking at the car from the front. The engine makes no noise. Only happens when you start moving and get's faster as you speed up.. When it began I heard nothing but the mild banging that got worse as I tried to drive it home. It does it both in forward and reverse. I had the Manual Transaxle fluid replaced about 6 months ago (6000 miles_ That's about all I can tell ya... Thanks for your insight..  

Answer
Richard,

It could be a CV joint or bearing that is going out since it does it when you are moving.  Also, there could be a defective motor mount.  You will need to get it on a lift and check it out to be sure.  If the fluid on the bellhousing is clear it is probably brake fluid from the clutch slave cylinder.  That would require a rebuild or a replacement.