Do I need these additives at my Mazda service?

My Mazda3 1.6 diesel is due for its second annual service shortly and has done 7300 miles. The garage says that Mazda recommends a bacterial cleanse of the ventilation system for £24.95 and a brake fluid change at £39.95, plus an engine flush and fuel treatment £23.45. Do these really need doing every two years, particularly at such a low mileage? I understand that it takes about five years for the brake fluid to get sufficient moisture to require a change and it can easily be monitored to allow the change only when required.
They are revenue streams for that particular garage. Brake fluid can be tested for moisture content and contamination easily at any service, and below a certain level it does not need to be changed.

If you are using decent diesel (Shell V-Power) then you don't need the engine flush and fuel treatment. If you haven't been, you might.

Simply running the a/c at maximum temperature for 10 minutes kills all the bacteria in the ducting.
Answered by Honest John on

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