Hey guys, just installed some jba headers on my 11 sierra today. Torqued everything down and all was well. On my way to work tonight, a small exhaust leak developed. I figured no biggie, just need to retorque. After driving about 100+ miles tonight, i let it cool outside at work. Before I left work, i torqued everything down again. The leak is better, but still there. Sounds like faint valvetrain clatter under load. I used the shitty paper/graphite gaskets that came with the headers against my own judgement. Should I just swap the factory MLS gaskets back in? Also, the driver side collector which is sealed with a metal crush ring from the factory fame with a graphite/paper gasket. The instructions didnt make any mention of it, so I just laud it on top of the y-pipe flange with the crush ring in place. Was that a no no? The leak seems to be from the driver's side. Im pretty set on throwing the MLS gaskets back in since ive never had issues in the past with them and headers. But I dont know if the jba collector flange will seal against the factory crush ring alone. Any ideas? Thanks!

 

Ditch the shitty paper gaskets and use a factory style MLS gasket. You should be able to reuse your factory stuff but getting new wouldn't be a bad idea.

 

Yep, put the stockers back on..

 

Think i should remove the gasket they sent for the driver's side collector as well? Or just change the manifold gaskets and see what that gets me?

 

Just manifold

 

I swapped out the manifold gaskets, surprisingly, the jba ones showed no signs of leakage. The leak is still there. I guess I'm gonna remove the gasket on the driver's collector and see what happens. But I also Hear it from the passenger side collector, the one that is just a flared fitting. Is there any way to seal those up other than some rtv?

 

I took out the collector gasket today. It fell out in pieces. I just reused the stock crush ring and it sealed up no problem!

 

Factory gaskets work the best.

 

I knew this from past experience, but for some dumb reason I decided to give the jba's a go...