I'm sometimes hearing a faint "whoop" sound from the transmission when changing up in low gears (1st & 2nd). Not sure whether to take it to a dealer or not. the vehicle has around 30,000 M. I have an extended warranty which covers the transmission but not diagnostic. The shifting isn't effected, just the sound worries me.

Any thoughts please?

Nester

 

There is a lot of information/history pertaining to this transmission on this forum. The TL;DR is that fluid changes are helpful and necessary, even if the standard answer is that it is sealed for life. You might want to search the various "Mercon SP" threads to get a sense of what the "consensus" is around these transmissions...

 

Agreed. Many refer to this issue as the infamous "ZF squawk". The solution is to do a drain-and-fill of your ZF 6HP26 transmission. You may need to do this a couple of times for the squawk to completely disappear. I concur using Mercon SP as your fresh ATF. Available at any Ford dealership. I run it in both of our Jaguars and it works perfectly....