2001 Opel Omega gear filter & the problem of slipping a

[quote:efb0d6f87a="aymen1"]Transmission problem
2001 Opel Omega 4 cyl Two Wheel Drive Automatic 190000 miles

sometimes my gear fails to change at 40k/h 2000 r/m two weeks ago a mechanic changes gear oil atf3 and cleaned the filter, but some say that I have to change the filter not cleaning, pls is it true that new filter will be ok and the changing will go smoothly?[/quote:efb0d6f87a]