I was looking at the "tattletales" or little strips of metal on the side of my manifold the other night and notices that they are bent pretty good, maybe a 20-30* angle. It is pretty rusty as well. How soon should I replace it? If I wait until it cracks, does the manifold crack or will it crack the block where it bolts in.

 

I have over 200K miles on mine with no problem. IF it does end up cracking it will just be the exhaust manifold that cracks.

 

188k no issues

 

225k all is good

 

can you post a picture?

 

I will get some pictures up asap. I was concerned that if it shrinks too much, it might crack the block. Good to know it won't!

 

107k and gone. I replaced it with an ATS. No damage to the block. Just a 3 inch crack on the manifold.

 

The manifolds usually crack at the outlet to the turbo, between the #3 and #4 runners. Mine was cracked about 85% all the way around, almost had a two piece manifold. It won't crack the block, because its not connected to the block. Its attached to the head. The 24v head has a lot of meat on it, the manifold is the weaker link. There are guys that have broken the ears off of a 12v head because of a expanding/contracting manifold. But thats pretty rare too.