"A lot of Corvettes suffer from bad clutch fluid, due to the seals. It's an inherent problem, even in low mileage cars-this one has 8,500 miles," says Tanner. Synthetic fluid offers a higher boiling point, which helps for open-track days because of the lines run by the headers. The downside is that synthetics are bad for the seals. Tanner therefore recommends using the factory fluid and changing it whenever it gets really dirty.