Cracked Cylinder Heads

I recently found out that the heads (both of them!!!!) on my 3.4L were cracked. The engine has never overheated so how did this happen? I thought that these engines were supposed to last? I only made it 190k and that seems to be a lot less than many others.

 

Are you the original owner?

 

yes

 

Was valve clearance ever checked or adjusted during the 190k?

Were the heads removed because of coolant consumption?

Often these cracks can exist for a long time without causing any real problems. Had them on my 3RZ head and have same on some VW heads, never would have known if the heads hadn't been off for other reasons.

 

don’t think valve clearance was ever checked nor adjusted. the car has been using a lot of coolant and it rough idles. coolant was found in the cylinders with the cracked cylinder heads.

 

Who can say a Flaw in the casting that just after this time worked into the combustion chamber.

The normal Thermal cycling of head temperature is enough

 

are there replacement aftermarket heads avalible or do you have to go new OEM?