This is what happens when oil becomes degraded by heat, pressure and oxidisation. This causes clutch wear, blockage of oil galleries and control solenoids. And that only touches briefly on what else can occur when oil becomes completely time expired.
Most tranmission rebuilders recommend oil changing on our gearboxes at intervals not exceeding 24k miles or two years which ever is the sooner. This is regardless of whether the gearbox is of ZF, Mercedes or Ford derived Bordeaux manufacture. Some may argue that such stringent maintainance is not neccesary or approved by Jaguar. Unfortunately many of us know from cold experience that neglect of transmission oil WILL MOST CERTAINLY result in the need for a rebuilt gearbox. All models of gearbox are servicable given the correct service equipment.
All models will benifit from keeping their oil in tip top condition and contrary to popular belief are not exempt from molecular breakdown once that expiry time has been reached. Continued use of broken down oil causes wear of internal components on an exponencial basis. The net effect being wear becomes greatly accelerated as the oil continues to degrade further. What is finally removed when a transmission fails is several bucket fulls of abrassive black semi solid sludge which will contain the wear down particulates of clutches, bearings and in extreme cases, large chunks of the gear train. My own gearbox suffered such a fate two years ago and cost £1600 to put right.
This link shows the contents of a Jaguar gearbox filter that has been opened following a transmission failure. It is not pleasant and what is shown on this short video is typical of the deprivations found in all makes and models of Jaguar failed gearboxes.
http://www.youtube.com/watch?v=yHny69FP ... B&index=17
Reference to page 48 of the June 2010 Club magazine gives further details on this ongoing gearbox problem.
The sealed for life issue is one that has caused considerable expense for all modern Jaguar owners over several years. "Sealed for life" was conceived by the marketing men. It over ruled common engineering principles and indeed common sense. After many years Main Dealers now accept that the concept was flawed and will change oil on their customers cars if requested. Many of those dealers do however farm that work out to accredited local transmission businesses who are better equiped to carry out this specialised work. Full flush oil drainage equipment will cost around £20k to install at a workshop and it follows that Main Dealers find it more cost effective to place such work in the hands of specialist companies.Expense can be saved by taking ones own car directly to a transmission repairer for service on overhaul. This would avoid paying a dealers mark up for handling the work.
Note also that repairs or rebuild of all transmissions used in modern Jaguars WILL require both the oil cooler and the torque converter to be cleaned out at the same time. The converter will be need to be cut open around its circumference, cleaned out, rewelded and rebalanced. Failure to effect such work will cause a newly rebuilt gearbox to fail again prematurely due to the abrassive contaminates from the unserviced converter being deposited in the rebuilt gearbox. The sad, sorry scenario of gearbox failure would then start all over again.
Later this year I understand our Club magazine will include an article I wrote with Mike Horlors assistance. It details the effects and causes of oil degradation and I hope will be of interest to all Jaguar owners whatever model they drive.
At the end of the day, the moral of the story is to keep up with regular oil changes and you will have done your best to keep wear to the minimum and prolong the life of your car. A stitch in time definately will save nine.
Mike
It sounds like a duff bearing noise which goes away when put in gear until driven when it returns again.