very hard shifts in a 92 300d

[1977busman]

So the car shifts hard, like at moderate acceleration it whips your head back. The lower the acceleration the less violent, but the hardshifts are still very noticeable. At full throttle its like whiplash... The car has done this since I bought it, and got a tiny bit better after a tranny fluid and filter change but not anywhere near normal. so what should I look for, i know nothing about these cars, and I dont know what would make it shift like this? And if the money was present this would be a perfect excuse for a 5speed... Also I wont be able to get back online till after 9 tonight to check this spread, just as an fyi...