I drive a 2002 Sable 3.0 Vulcan w/ 121,000 miles, and my tranny has been leaking alot the last few days. At first I felt it slipping whenever I made a turn and checked the fluid, it was low so I thought some trans stop-leak added to the extra fluid would help, it didn't. Now the damn car leaves a small puddle every place I stop and the slipping is worse. I noticed it slips the most when I make left turns, not so much when going right, if that helps any. Is it common for the trans pan gasket/seal to fail? I haven't had a chance to check where the leak is coming from but I would guess thats where its leaking at. Any thoughts?