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and be sure the bolts are the right hardness

I got the 10.9 same as the existing, high carbon content, too brittle in my opinion, Being torqued to 15 ft lbs seems like some serious expansion needs to happen to pop a head off, but we will see.
I followed the pattern 3 times @ 15 ft lbs,

Thank you to everyone for the great information and fast response.
I will keep you posted if there are any more problems.
John

Quote:

Originally Posted by jonnieh3 (Post 239640)

Thanks for the quick reply,

Any reason for the heads to be breaking off this is the second time this has had to be repaired, The dealer did it whan I got it at 30,000 mi. and now at 56,000. I do not think it was one of the previous ones and they put all new bolts in last time, ( because they left the old ones in the wiper recess area)
It was the center one, The head shears off the bolt and there is about 3/8" of the bolt sticking out of the block. Total PITA to do.

I know this post is years old but just in case anyone comes across it and wants an answer to this question, it is a very common problem and should have been recalled by GM.