I have 71k on my 2000 LC and I'm thinking about taking it in for preventive maintenance as I will be hauling a heavy boat from Florida to Illinois next month. TB has never been done and the usual discussions here are based on miles. I know I'm beyond the 9 years, but is the TB wear more due to mileage or year? My gut says to have the TB, water pump, etc. changed as a precaution, but I just wanted to verify that I shouldn't wait the additional 3 years till I get to 90k.