Well I am caught in the middle of changing diff. lube, didnt do my homework, dont know if I have limited slip or not, bought used from private owner. Need truck in morning 150 miles to Doctors appointment. Can you tell if it is limited slip. My equip. tag says spicer 70, the diff just says Dana. Its a 98 24 valve quad. auto. Tried to find answer through search but no luck. Need to know if i need that friction modifier or not? Would it hurt to drive without it a bit? HHHHEEEEEEELLLLLPPPPPPP!