I noticed fuild coming from transaxle housing next to motor block at the top of housing that connects to the block. Looked as through a valve on the housing was LEAKING BADLY,from top of the unit. I was told this maybe a pressure valve. Transmisson moves in reverse not well in drive. What is this? Again this is my 1999 Buick LaSabre v6 3800 series.

I am not sure where exactly on top it is leaking, so Possibly this diagram may help.

A picture would be helpful.

Looking at this diagram I would say 405 Low Blow off Ball Valve Bore Plug, 406 Low Blow off Ball Valve Spring or 420a Low Blow off Ball Valve. Do you have any suggestions?

As Mike Mentioned, a photo would be beneficial.
Or even a video so we can see the leak in action!
Look closer and confirm to see if the bore plug is actually missing.

Approx. area?

I can't tell from this view. It'* been raining all day here, I will being trying to video it tomorrow. Thanks for your interest.

I'm working on getting a video of what it'* doing. It has rained all day here, tomorrow I'll give it a shot. Thanks for your interest.

I'm not very computer friendly can someone assist me in getting a video put on here?

Put it on Youtube, then copy the url link into the comments here.