ddbrown

My 2003 XLT with 4.2L has 119,000 miles on it and I just had the cooling system flushed, replaced all hoses, thermostat and water pump. About the same time my serpentine belt started squealing upon startup for a few seconds. About a week later I replaced the belt and it got worse and would last longer. I would have to drive about 15 minutes until it quietened down. My local auto shop who I have a good relationship with tried replacing the tensioner assembly and idler pulley separately thinking it was one of them since I had a new belt. No change so they tried another new belt and it went away...Both the tensioner and idler pulley were fine so they put them back on...no charge for anything. belt was under warranty and they treated the parts swap as diagnostic. ..Mechanic tile me he has had to go through 4-5 belts to stop the squealing (after confirming no mechanical issues)