Does my Peugeot 407 really need diesel fuel additive?

In my 2006 Peugeot 407 SW SE, diesel fuel additive should be checked at 70,000 miles and running out can lead to massive bills. Mine required three litres of additive at 65,000 miles at a cost of £75. Another 'expert' told me this is totally unnecessary. The system assumes each fuel fill is a full tank, not a top-up, therefore the additive is used up well before 70,000 miles and no damage results under normal driving conditions. Also, he said many drivers refill the additive tank with diesel fuel and suffer no ill effects. Finally, the additive itself is not a high-tech, high-cost fluid and is therefore vastly overpriced. Is there an independent comment on this please?
Your expert does not know what he is talking about. The Peugeot/Citroen system relies on Eolys fluid to regenerate the DPF. That's what cost £75. But the DPF itself is unlikely to last longer than around 120,000 miles and they cost about £500 to replace. Plus another tank of Eloys fluid, of course.
Answered by Honest John on

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