exhaust manifold bolts

[HeavyDutyChevy]

Hi I have 02 Silverado 2500HD 6.0L. The other day I notice the very back bolt that bolts exhaust manifold to cylinder head the head of bolt was gone on both sides. I was wondering what size is bolt. Its a flanged head with small hex head bolt. I just need to know what size bolt is. Thanks.

[dougmac]

Hi I have 02 Silverado 2500HD 6.0L. The other day I notice the very back bolt that bolts exhaust manifold to cylinder head the head of bolt was gone on both sides. I was wondering what size is bolt. Its a flanged head with small hex head bolt. I just need to know what size bolt is. Thanks.

 

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GM engines are assembled using JIS metric flange bolts. My experience has been that they are very difficult to find in the after-market. You may be able to find them at a specialty nut and bolt seller but you probably won’t be able to find them at your local parts store. Because of the heat involved you will want to get the bolt that was designed to be there. I would go to the dealer to get them.

 

JIS has become a very popular bolt standard for many years. It’s baffling that they are so difficult to buy. This frustrates me every time I have to go to the dealer to replace a simple bolt.

 

Doug

[Mr. Smith]

Hi I have 02 Silverado 2500HD 6.0L. The other day I notice the very back bolt that bolts exhaust manifold to cylinder head the head of bolt was gone on both sides. I was wondering what size is bolt. Its a flanged head with small hex head bolt. I just need to know what size bolt is. Thanks.

 

<{POST_SNAPBACK}>

 

 

 

On the older engines they are SAE 5/16ths thread pitch if I remember correctly. Even though the head is metric the threads are SAE. The same may be in your case. Did the old ones break off as you will have to get the old one out and you could use it as a sample to match it up.