View Full Version : The Ticking Knock

04-06-2007, 01:10 AM
Just recently I have noticed a significant noise in my truck. It is a 98 S-10 vortec v6 with 74xxx miles on it. It is my DD and I do treat it well and change oil regularly. I believe that it has something to do with valve train, not sure. I always run medium grade octane and about once a month I run 93. Is this an oil problem or a fuel problem? My oil readings have been normal. I do have a 2 gallon mixture of 93 with xylol. Would it be safe to run it? Will it harm the engine? I'm thinking its an low octane problem but I don't know why. I never hear it when its parked in the driveway. I only hear it while driving. Any and all advice will be appreciated.