When should coolant be replaced?

I have a 2007 Jaguar XJ 3.0-litre V6 with 44,000 on the clock. Jaguar are saying that the engine coolant needs replacing at this service and are quoting over £100 to do it. When should the coolant be replaced and do you think this is a reasonable price?
That is a perfectly reasonable suggestion and a reasonable cost. After 10 years, the corrosion inhibitors in the coolant will have degraded and it will have lost some of its anti-freeze properties as well.
Answered by Honest John on

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