exhaust leak, again

[Familyman2112]

Hello from the frozen Midwest! My 2011 Denali with 95,000 miles is really starting to frustrate me. I had a cracked exhaust manifold. I didn’t want to mess with it so I brought it to a shop I trust. He recommended doing both at the same time and gave me a decent price, so I did. Now comes the headscratcher. Every few weeks or so since they were installed I get an exhaust leak on the driver’s side. The shop has tried several things to keep the bolts tight, but it still happens.

Anybody have similar issues with the 6.2? I’m wondering if I would be better off going with headers. I would greatly appreciate any advice.

Thank you! Stay warm, it’s freaking cold out here.

 

[Geotrash]

Hello from the frozen Midwest! My 2011 Denali with 95,000 miles is really starting to frustrate me. I had a cracked exhaust manifold. I didn’t want to mess with it so I brought it to a shop I trust. He recommended doing both at the same time and gave me a decent price, so I did. Now comes the headscratcher. Every few weeks or so since they were installed I get an exhaust leak on the driver’s side. The shop has tried several things to keep the bolts tight, but it still happens.

Anybody have similar issues with the 6.2? I’m wondering if I would be better off going with headers. I would greatly appreciate any advice.

Thank you! Stay warm, it’s freaking cold out here.

Nothing quite like that, but when I did my cam swap and had the heads off in my 2012, I reassembled everything with ARP chromoly exhaust manifold bolts and they’re solid. These manifolds will pop a head off of one of the factory bolts every 100K miles or so. Yours is the first I’ve heard of a manifold cracking. Might have the shop try the ARP bolts next time.

 

[Fless]

x2 on the ARP bolts, sooner than later, since you can still get those bolts out whole.

 

[swathdiver]

Hello from the frozen Midwest! My 2011 Denali with 95,000 miles is really starting to frustrate me. I had a cracked exhaust manifold. I didn’t want to mess with it so I brought it to a shop I trust. He recommended doing both at the same time and gave me a decent price, so I did. Now comes the headscratcher. Every few weeks or so since they were installed I get an exhaust leak on the driver’s side. The shop has tried several things to keep the bolts tight, but it still happens.

Anybody have similar issues with the 6.2? I’m wondering if I would be better off going with headers. I would greatly appreciate any advice.

Thank you! Stay warm, it’s freaking cold out here.

Did they really replace the manifold on the driver's side? Where exactly is it leaking from? Cylinder head or Y-Pipe?

What brand of gaskets did they use? Fel-Pro, Victor and Ultra-Power gaskets don't take kindly to warped flanges. GM and Mahle do.

A few years ago mine sprung a leak on the passenger side and since I was recovering from surgery I took it to a shop for repair. The owner of the shop discovered that the flange had warped and spent a good amount of time planing it smooth again. This might be your case.

 

[drakon543]

as far as the bolts coming loose on manifolds and headers all the time. fear of snapping them after the number of times ive had to extract them has always kept me from beasting them in. i started using the orange rtv on the threads and that always seemed to help.

 

[donjetman]

Hello from the frozen Midwest! My 2011 Denali with 95,000 miles is really starting to frustrate me. I had a cracked exhaust manifold. I didn’t want to mess with it so I brought it to a shop I trust. He recommended doing both at the same time and gave me a decent price, so I did. Now comes the headscratcher. Every few weeks or so since they were installed I get an exhaust leak on the driver’s side. The shop has tried several things to keep the bolts tight, but it still happens.

Anybody have similar issues with the 6.2? I’m wondering if I would be better off going with headers. I would greatly appreciate any advice.

Thank you! Stay warm, it’s freaking cold out here.

You might wanna try "Stage 8 Locking Fasteners" sold at summitracing.com etc.