Jaguar 2.5 Auto AWD 2001 Model 62000 Miles – Loss of all drive.

Car has had no historic problems other than a small leak from the transfer box, seal replaced and problem cured.

Today, after about 15 Miles of Motorway, there was a ‘Whirring Noise’ and the Rev Counter Needle started to ‘Bounce or Oscillate’ and all of this was accompanied by a feeling of “loss of drive”. Car was driven slowly off motorway and eventually all drive was lost. Car was turned off and re-started after 20 Mins, drive was present for about 20 yards. Car now recovered home and after 4 hours of ‘cooling off’ would only move about 4 feet before all drive lost. No warning lights on dash, car starts fine and revs OK, no drive, nothing, no matter what mode, std, sports, manual gear selection, nothing.

Any ideas, common probs (i'm quite technically minded so no 'take it down the dealers' type answers please folks) ?