SD.Kfz.251 drives only 10Kmh!

Yesterday we were going around to visit other Servers and testing the Transports. We noticed that on full Servers with High Pings the Sd.Kfz.151 gets stuck at 10Kmh and you don`t see the animation that the driver uses the "Gangschaltung" to put in a higher "Gang" (Sorry don`t know the english Word for it). They were fast as a Turtle and some guys at ubb server were very angry. I´m not sure if this is related to high ping

or a real bug. It is really annoying and the Guys were frustrated. It`s on every Map happend which has transports.