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Chevy Trailblazer 2008 LTZ (4.2L)
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Exhaust Manifold bolts GM P/N 11609481 (11pcs) (the size m8x1.25x33, 23. 9)

image.jpg image2.jpg
You should not use old bolts.
They underwent heat treatment for a long time and there is a high probability that if you install them again then the next time they are unscrewed, they will burst. I also don’t recommend using size-appropriate bolts, for the original bolts the tensile strength is 9.8 (you can see these numbers on the head of the bolt) I think the bolts that are sold in a regular store are much weaker. You risk that they burst in the future.
 

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2003 chevy trailblazer_ltz
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153 Posts
The FIRST time I changed manifolds, I bought new metric bolts at the local home-improvement store.

Post 115.

Downside is that all the photos I posted seem to be gone.
 

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2003 chevy trailblazer_ltz
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153 Posts
Exhaust Manifold bolts GM P/N 11609481 (11pcs) (the size m8x1.25x33, 23. 9)

View attachment 55150 View attachment 55151
You should not use old bolts.
They underwent heat treatment for a long time and there is a high probability that if you install them again then the next time they are unscrewed, they will burst. I also don’t recommend using size-appropriate bolts, for the original bolts the tensile strength is 9.8 (you can see these numbers on the head of the bolt) I think the bolts that are sold in a regular store are much weaker. You risk that they burst in the future.
The bolts I bought at the home-improvement store, and the Dorman bolts are STRONGER than the crappy GM bolts. GM = 9.8; aftermarket bolts were 10.9. The hardware store bolts were 35mm long, a 5/16 washer gave the same thread engagement as the original 33mm long bolts.
 

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Chevy Trailblazer 2008 LTZ (4.2L)
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aftermarket bolts were 10.9. The hardware store bolts were 35mm long, a 5/16 washer gave the same thread engagement as the original 33mm long bolts.
I hope that aftermarket bolts with a 10.9 index is really true. Sometimes this inscription is not true :(
 

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I hope that aftermarket bolts with a 10.9 index is really true. Sometimes this inscription is not true :(
Absolutely possible that the markings are false. The Communists are NOT to be trusted. They have a long and terrifying history of lying, deceiving, covering-up. They're "ethically challenged" to say the least.
 

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2007 Trailblazer LT
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86 Posts
Discussion Starter #27
I bought the bolts online today just incase. Better to be fully prepared.
 

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2007 Trailblazer LT
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Discussion Starter #28
Good thing my manifold arrived safely today as even the heat shield thing has rusted off and fallen apart! Tore it off today and tossed it while trying to get a look at the crack.... which is quite large. When those bolts arrive I'm ready to go.
 

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2007 Trailblazer LT
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Discussion Starter #29
Soooo..... My Dorman manifold kit came MISSING the three studs and nuts for the downpipe connection...I emailed Dorman but may not hear back for a while. Should I not get any reply and have to source these elsewhere....are theses the right size?

 

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Chevy Trailblazer 2008 LTZ (4.2L)
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Do you need № 10 studs in the diagram?
If YES then DORMAN is consistent with this. Original Part Number GM P/N 11589264
P.S Sorry, sometimes the translator translates the text very poorly and therefore I am attaching a scheme, this does not allow mistakes.
Exhaust manifold 4.2L.jpg
 
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