The used car I want to buy is within mileage limits for servicing but out of time (servicing is 20k or 1 year) - it was serviced at 20k 1 year 9 months ago. It is nearly three years old and now has 25k miles. Dealer has offered to get it serviced and provide replacement warranty if manufacturers' is invalidated (5 year manufacturers). Is this reasonable?, what are the pitfalls of time related service delays for a 2.0 diesel?