We have just had a week in Cornwall,during which the car performed faultlessly. However on the return journey after driving through some horrendous weather we had a clear run up the M5,until we left the m/way at junction 3,I came down the slip road over the first set of lights,second set were against me so slowed up to stop,just before stopping the g/box changed down with a hell of a thump. When I pulled away the box was reticent to change up, after revving in bottom gear for a few yards it changed up and has worked perfectly since.This gearbox has always been a smooth as silk. Anyone any ideas??

Hi Mike,

What mileage has the car done overall?

Judging by the year you'll have the six-speed gearbox which is supposed to be much better than the five-speed box which had some serious problems - I bought my first S Type in 2001 and the gearbox failed totally about 5 years in at 78,000 miles and coincidentally a mate of mine who ran an XK using the same box lost his at about the same mileage. That said there are many S Types out there that have done 125K plus without problems.

Based on your experience it may be that the box is low on oil or the filter may not be performing as well as it should.  Jaguar make no recommendations regarding gearbox oil and filter changes and is not included in the service regime but many S Type owners, me included, think its worth the expense of getting this done. It's a tad expensive, circa £200, but much better than a £4-5K replacement box. There is an additional benefit of doing the change because the old oil, sump pan and integrated filter can be checked to see if there are significant amounts of metal present resulting from wear someplace in the geardtrain.

In the meantime I would be watching for a heavy thump as you select Drive or Reverse.

Hope this helps.

Hi

How long have you had the car

this was a known issue with software in the gearbox and updates sorted it

there was known issues with 1st to 2nd and 2nd to 1st, there was also issues with surging when the gearbox was warming up

If you have the gearbox serviced at Jaguar they update the gearbox and reset adatations when they do the filter, oil and sleeve service on the gearbox

gearbox service usually makes it drive smoother, sounds like it shifted to 1st to harsh, so could be software

I'd wait and see if it gets worse

cheers

Joe

Thank you all, I have had the car for nearly two years ,the gear box had an oil change just before I bought it,I checked with the dealer that did it. Since it threw its little wobbly it has been no problem ,as smooth as ever..It is perhaps a little slow to drop a gear at speed ,but that could just be me sitting too far away from the pedals !!!!!!