i tend to notice that the car tends to "jolt" a bit downshifting, in particular when i am not driving so fast. say accelerating to 25 mph and rolling to a stop sign, i will feel the downshift. i do not consider it a very serious jolt, but certainly something that i do feel. i recently had the dealership run a test on the transmission as it gave me problems in the cold and was told nothing was wrong with it. i have a 1999 323i with 44,000 miles on it. if you are getting the same issue, i wouldnt worry about it.