yea this post is almost a year old but i figure ill toss in my 2 cents. i too just bought a 01 cobra, extremely clean with 48k miles. my shifting was also notchy and just not quite right. after combing forums for hours, i jacked the car up and pulled the drain plug. i pulled over 5 quarts of fluid out of the tranny which is WAY to much. after searching for what type of fluid to put in it, i settled on this. i put exactly 3.2 quarts of pennzoil synchromesh in it and took it for a ride. my shifts now are smooth as silk. a complete night and day difference on what it was before. ive read people running 3.2-3.8 quarts and are fine but you DONT fill these things until fluid runs out of the hole like other manual transmissions. just measure it out and you'll be fine. hope this helps