2002 gmc yukon 5.3 engine knocks when starts 247000 miles on it started at 40000 miles
Dec 12, 2010 at 9:10 PM
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these are well knownfor this when cold. the kock usually goes awasy and it sounds like a tapping it is probably piston knock or slap. have a pro listen to it. it won't hurt anything doing that just aggravating