I have seen threads with a part number for an additive for transmission fluid but cant find it now. I was going to change the tranny fluid first. Any other ideas on what could cause this or what those part numbers are?

 

The ZF additive to cure the "bark" is Part No. C2C37157. Forum sponsor Nalley Jaguar in Atlanta was selling it to forum members in September 2010 for $40.72 with free shipping. You may want to call them for up-to-date info (800-846-0030). It's a one-litre bottle, so you drain one litre of your ZF Fluid and hand-pump this magic juice (I believe ZF calls it Lifeguard 1) into your transmission pan. The Jaguar TSB for the procedure is JTB00070, dated November 29, 2007. Those who have done it have generally reported here that it works....

Our ZF was "barking" sporadically during the summer of 2010, but once the weather cooled down upon autumn's arrival, the bark disappeared and has not returned. So I have not performed this action yet, and hope I don't have to....

 

Thanks. I called them up and and still got that price.