Just come back from a trip to France and I had clutch slip - why? Clutch slipped when going up steep hills towing a 300kilo trailer and cruise control on. Slip happened when the cruise control accelerated us up the hill. When I switched autocruise off, it was difficult to get the clutch to slip - got it to do it once. Before thr trip I had the engine remapped ( Peugeot 2.8TDI ) and the cruise control fitted. Now that we're back, without a trailer i cannot get the clutch to slip at all. Is the clutch damaged? Is the remapped engine too powerful for the clutch? Is the cruise control too aggressive when accelerating? I just can't work it out. The van has 25k on the clock and I have already had a new clutch assembly at 15k when the pressure plate went soft through a broken spline . This time the clutch is holding much better than when the pressure plate was soft - so guess it's not that. It will cost a lot to drop the gearbox to see what is going on. Any insights?