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My wife has the above car - 1999 year, diesel engine. On a long, fully laden, trip through France last year it suddenly developed a severe shuddering under load - either accelerating gently or going up a hill.

I could stop it instantly by changing the revs, either by taking my foot off the gas, or increasing the engine revs by accelerating hard (so it auto downshifted) - or dropping it into manual and going down a gear.

Normal driving - ie: gently cruising around - is no trouble. It's only when there is a bit of weight on board or going up a reasonably steep hill that it starts shuddering. By holding the revs I can get it to shudder quite badly but any rev adjustment and it goes away.

Unfortunately, the rev range is not always the same - it's around 2k but can vary considerably from there.

I had a mechanic look at it and he thought it might be the engine mounts so changed them but it's made no difference. Wheels are all balanced and there is no apparent wear in bearings, cv joints etc.

I sort of assumed it was the transmission packing up but it's got no worse over the last 16 months and, other than the problem, behaves fine. The engine runs sweet and revs freely out of gear with no vibrations.

Does anyone have any ideas what might be the cause before I despair?

Also, yesterday, the dipped headlights (both) packed up. All other lights work fine and I've checked the fuses mounted in the dash which are all intact. The footwell fuse chart is missing so I've no idea if there is another fuse or relay but I did visually check them (well, the fuses anyway) and they all seem intact. I managed to get one headlight lamp out of the stupidly designed housing and tested it - fine - so it's not the lamps themselves.

Again, anyone have any ideas?

Thanks in advance.
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