Hello guys,

i am new on this forum and i have a problem regarding my gearbox.
3 months ago i gave my car to official service to change my gerbox oil cause i bought my signum half year ago. To be sure, that my signum will run more smooth i changed quiet a bit of old parts all made by official service in my country - Slovenia.
Car was great, its motor runned like new engine, gear shifting was great , everything was great before i went to service.
After they changed; engine oil, filters, gerbox oil, rear discs + pads, cooling liquid, end much more, the car is not the same.
Its engine runs like old tractor, my consuption rised from 6,2 to 7,9 liters/100 km, and the biggest problem (the reason i write and cry for help) is gearbox.
When i drive it in D, normaly its shifting cannot be sented, but now after he change the gear it bounce (i dont know the right word in english for it) feels like someone hit you from behind while parking.
I went back, they told me that everything is ok and i dont have to worry about it.
I am bloddy worry because, it seems to be another car and i dont enjoy anymore, cuz i am afraid something can go very wrong bout gearbox.
I ask you guyz, does enyone have a clue what could that be, what i must do.

Thank You

p.s. - sorry for bad english