NZ ,Mark a spot on the backing plate and the brake drum with a bright color on the inside of the wheel as if you were under it by the gas tank. .Now do the same with the drive shaft yoke. Mark a spot on the 3rd member housing and the yoke. Now in one revoulation( 1 rev. will be one full turn on the mark you put on your back plate/brake drum) count the number of turns the drive shaft yoke spins. 3 and a half drive shaft rotaions in one revoultion on the marks you made on the brake drum would mean you have 3.55's. patriot