Road Race Upgrade Option We use polished internals, vented boots, and high temp grease. Standard grease liquefies at 300 degrees Fahrenheit, the high temp grease has a much higher break down temp. We have a vented boot that keeps the boot from expanding. The benefits are keeping c.v. temps down, Which pro longs axle life and boot life. In road race settings axle failure 9 times out of 10 caused by high temperatures in the c.v’s.