FTBR install with 3:73 gears and FR diff cover. After this I went on the track and the pinion seal began to leak major. Installed a new seal and the same thing happened. This didn't happen on the street, only on the track. The pinion angle is correct, no vibrations or noise. The vent tube is clear. I was told to much heat and pressure at track speeds and need to install a expansion tank? Anyone had this issue?