Hello! I bought my 2001 XK8 in Feb of this year with 85k miles on it. I have some records from the PO, but they are spotty. When I try to use the manual side of the shifter, it gives me a transmission fault warning. If I turn the car off and just put it in D, it drives great and shifts just fine. I have now put 5000 trouble free miles on the car, so I'm thinking I might change the trans fluid, since I have no idea when it was last changed, if at all.

I'm considering doing a simple drain and fill to start with, then a complete flush in a year, when I'll replace the filter (especially if this doesn't fix the error problem).

I want to do this in order to avoid shocking the system if it's never been done.

If I do the simple drain and fill, can I use Valvoline Maxlife or some other equivalent to the original Esso LT71141 fluid?

 

As all is well in D - drive, it may be worth looking first at the J Gate gear stick module. Lots of microswitches in there that could be the source of the warning. Easy DIY check with a sticky thread with the Rev Sam Youtube video.

I’ve an old pic below looking at the J Gate module parts

 

Before you change the transmission fluid, you might want to peruse the thread: https://www.jaguarforums.com/forum/x...ts-data-29800/

There's a wealth of information in there about our transmissions and fluid requirements.