8.1 Vortec
Has anyone had problems with exhaust manifold leaking or cracking.
Forum Discussion
- Yes; several have reported so.
- Mine is fine at 73K miles. My brother has the same engine on an older Yukon, no problems as far as I know.
- A common problem on them,I had 4 sets replaced all under warranty.
If it is fairly new it may be covered. They made some new models with a cut between each exhaust ports that seemed to work for awhile. The other fix was to put headers on,not an option here in California due to smog regulations.
I was told by my RV mechanic that it was more common on RVs than in other applications is because of the limited air flow around the engine,the 8.1 runs very hot exhaust temps tending to warp the manifold. - 107k miles on my 02 no problems
- 75,000 on our '04 workhorse and no problem.
- A Google search shows it to be a fairly common issue, along with broken manifold bolts.
- More likely if:
1. Engine compartment air flow is restricted, like in a Van or Class C RV
2. Engine is Big Block like Chevy 454, 8.1, and Ford 460, bigger parts amplify the expansion differences between the heavy head and the light manifold. Ford V10 too, it's a small block but the extra cylinder on each side makes it another "long" engine.
3. It's working hard, Motorhome or Towing. I wouldn't expect daily drivers or lightly loaded RV applications to have the problems a large Class C might. - Broken studs on ours, I installed headers so I wouldn't have to deal with it again.
IAMICHABOD wrote:
...The other fix was to put headers on,not an option here in California due to smog regulations...
Don't understand. All emissions controls are still intact on ours after installing headers. Catalytic converters, O2 sensors, EGR, etc. Only change was to replace exhaust manifolds and section of exhaust pipes with headers and new pipes. IAMICHABOD wrote:
The other fix was to put headers on,not an option here in California due to smog regulations.
There are approved headers and other aftermarket performance parts available that do meet the Cali requirements.
https://www.smogtips.com/aftermarket-performance-parts.cfm- I know the early 6.0's had issues (mine my 02) with header bolts breaking resulting in leaks.
