Good morning I just signed up today. 2005 Armada. Cracked manifolds. Very low budget but I ordered a set of original similar not headers. My question is why isn't there a flex pipe in these things, they are mounted solid and there's a lot of weight hanging off the end of that manifold. I am a long ways from being an engineer I admit that. But it looks to me like the vibration would break them more so than the heat. With the torque of the engine raising and lowering the exhaust system I think there needs to be room for movement in the exhaust pipes. I've read forms up one side and down the other and don't see where anyone has had this thought. My new parts will be in this week. If there's some reason I should be discouraged from putting flex pipes in below the first cat's let me know. And I thank you very much for your time.