I own 3 Jaguars. 2003 xk8 and 2 2004 xj8. Both xj8s have had additive added to the transmission to stop what the dealer calls Transmission Whoop. It worked for a year or 2, but has come back in a minor way in both cars. The xk8 was not treated and makes a little noise.
The question is---is this just an annoying sound, or is it the sound of damage being done. I can easily live with the sound if that's all it is.