Exhaust hardware ?

[grcthird]

Anybody see anything wrong with using grade 8 bolts on an exhaust manifold? I had a factory bolt in my dd shear off the other day, 06 GMC 4.3 sierra. I pulled it last night and I'm about to hit the machine shop with it.


And just for the awesomeness factor, I drilled it then promptly broke the extractor off in the head.

 

[pheany]

Do not use grade 8, the heat will weaken it. What you need to do is find stainless steel bolts since your heads are aluminum on that truck. I have a 4.2 vortec in my trailblazer and the front 7 bolts kept loosening, so i took them out and replaced them with stainless bolts with a stainless lock washer, and put on some anti-seize.

 

[grcthird]

The heads on mine are cast iron, and I thought about stainless just to deter the rust factor but stainless is softer than grade 8 stuff. They'll definitely get some anti seize as will the ones on the other side.

 

[draggbody]

buy some stage 8 fasteners... anti sieze and forget about them... btw i use grade 8 when needed...