Help, Tiptronic Backs

Hello people, hope to get help from you again.. since today my Tiptronic moves very gently in the 4th gear and gives a little more gas, without forcing the gearbox to shut down, then I feel during the acceleration 1-2- to 3 clear spines. At Kickdown everything is ok. It doesn’t matter whether in automatic mode or in tip mode. Rotational zal between 1500-2000 (so I always ride really) driving style rather sneaker than raser. Should I fear the worst By the way, was recently with the friendly one to ask if ATM oil change would be good for the transmission – he said the ZF transmission is problem-free as a rule, is not necessary.