Weird problem: Juju's '94 CS convertible has a transverse rear leaf spring made of carbon fiber. Squeaks. Badly. All you Engineer types on CO, what should I use to moisten it, and get rid of the obnoxious squeak? Had shop owner put it on the rack today and he used something (that I can't buy) on the ends, and it quit. By the time I got home at 70 MPH/14 miles), started again. He also stuffed some of that strawberry Valvoline thick grease in there. Opinions, please.