Brake Rotor, Rear. FITS 1986-1988 XJS With Dana Differential. For the Dana differential. The Dana differential can be identified easily, as it has a three-bolt axle flange and does not have a bottom drain plug. (The Salisbury/Gkn differential unit has a five-bolt axle flange and a drain plug, and uses part number JLM730.) (JLM731)