I changed the gearbox oil on my 323 its very easy i used Fuchs Titan 75w90 and since then the gear changes are really smooth even when the box is cold its well worth doing. As for the clunks it seems its a very common problem on e46 mine does it even after i changed the guibo which is meant to be one of the many sources. The diff bushing and subframe bushes are the next to be done.....heres hoping to a non cracked body. :huh: