The Princess had her transmission sump, filter and fluid replaced today and it certainly was worth the time and effort. She has done in excess of 135 000 miles but, as far as I was concerned, the transmission was faultless apart from occasionally seeming to slip, or take a while to match engine speed. Once or twice I've had the "gearbox fault" caption as well, when accelerating hard when the car was cold. Time will tell but I'm confident that has been sorted out. After the change, there is no longer any apparent slipping and, one thing which I was concerned about, which was the time delay between flooring the throttle from low speed and feeling the kick in the back, which I had assumed was down to the age of the engine, has now completely disappeared :D Clearly, the engine wasn't at fault but rather it was an insidious symptom of the transmission. 4.5 litres of black, burnt treacle was drained, and 6.75 litres of new fluid was added, along with a brand new sump and filter and gasket. There was no indication of leakage of transmission fluid but the original sump pan was certainly warped. The sump pan, fluid, filter & gasket set cost me £120 from a fleabay dealer and my mechanic charged me £40 to do the job, including checking the fluid level in the approved manner. Happy bunny :D I am now, even more than previously, sceptical of the "filled for life" philosophy, having seen how little fluid was recovered and the state of it. Instantaneous response is nice as well I am also expecting better fuel economy now that the engine doesn't over-rev but how much, or indeed, whether it will be measurable, remains to be seen.