STS Over Heating

[jba53]

My 97 STS started over heating when put under a load going up in the mountains. It never over heats in town even when left to idle for prolong periods of time. A mechanic said the head bolt threads start to pull causing a build up of pressure in the cooling system and is a $4,000.00 fix. Anyone heard of such a thing??

JB

 

[MAC1]

First of all, how did the mechanic arrive at his conclusion that the head bolts pulled? Did he check the antifreeze for combustion gases? While it's possible that you have a blown head gasket, there are other possibilities including a bad thermostat or a clogged air purge line.