I would just like to say "thank you" for the earlier posts as it has helped me to understand a lot more about this subject. I have had the warning a couple of times on my 5 year old/75,000 C5 and at the service last week the garage said I would need a new filter and new fluid. They will give me a quote on Monday, but it sounded as if it would be around £400. It seems that I have been lucky to get to 75,000 miles before this needed doing. If anyone has had this job done and could let me know what the cost was, I would be grateful.