Not true about the lead additives wearing motors out, that is a bunch of horse pucky spouted by a lot of the enviormental haters If you go back to the engines made originally in this country for our cars and trucks before the lead additives where being used in the fuel the motors needed valve and ring jobs long before 30,000 to 50,000 miles The lead additives added to the gas stop the need for the valve jobs and also help increase the ring life along with better valve life The lead additives, Tetra Ethel (SP?) was a lubricant for the valve seats and cylinder walls that reduce metal to metal wear, it didn't increase the engine wear