My GMC Z71 with the 5.3L engine has 136,000 miles has developed a slow coolant leak. At about 130,000 miles I changed the water pump which was original just as a precaution and the thought that it was the cuprit for the slow leak. Now 6000 miles later the coolant level is low again. I've read that the DEX cool can deterioriate the Intake manifold gaskets but I see no evidence of a leak on the external portion of the intake nor can I see any evidence in the oil that the gasket has failed to the inside of the manifold. Any suggestions?
Saturday, March 10th, 2007 AT 10:51 AM