bblee

Hey my s5 automatic is slipping gears badly need help on what ya think it is... my first transmission was slipping bad so i went and bought a use tranmsision and this guy swap it out for me and it still does the same exact thing... im thinking maybe its not the transmission that is bad cause both the transmission is doing the same exact thing. i was saying that if one of the transmission is bad the if should have different slipping problems but it has the same exact problem so im thinking its not the transmission but something else... if anyone can help me with this i would really appriciate it i been having this problem for awhile now and want it to be running right... Thanks...