So does the car pull the van up a hill /driveway in forward using command shift.
I have been reading about an issue with my D3 on the UK site and from what you describe I would say its gearbox related.
Have you had the oil changed at all or is it still on original?
Do you notice any fluctuations on the tacho?
Seems by your list you've covered most of the engine but unless I missed it I didn't see any gearbox item mentioned.
Bulletman
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