maik

As the title says, I've got another leak from my passenger exhaust manifold. I've replaced it 3 times. Last time I replaced it the manifold gasket near the front cylinder was actually rusted/corroded/falling apart. I replaced the manifold and gaskets about this time last year and it started again a few months ago, and after doing the soapy water test the leak is coming from the same area.

Every time I've replaced it it's been with a Dorman kit off of RockAuto. I'm not sure if I'm battling crappy aftermarket parts, an uneven head surface, or maybe a bit of both. Every time I replace it the truck is nice and quiet for 8 months or so and then it gets bad again.

Any recommendations here? I have no interest in pulling the head to have it checked, but I also don't want to keep replacing it every year (though I've mastered getting the top starter bolt in and out now).

My truck is a 2009 5.4L SuperCrew FX4.

SALEEN961

iTrader: (1)

I've installed a few of those Dorman manifolds and talked to a Dorman quality assurance engineer and had him come out to the shop to inspect the install. Long story short they don't manufacture their own parts, they subcontract manufacturing to foundries in China for the most part. Upon looking at the manifold that I had crack after 1500miles he was furious because the manifold was made out of the wrong material and was recalled, but was still sold to us. Dorman's quality control sucks and their parts while good enough to fix a car short term to sell it are generally not what I use on any vehicle I planned on keeping. There are a few exceptions to this rule in their catalog, but there aren't many.

Pull the manifold off and put a straight edge on the manifold and cylinder head to determine if either are warped. If everything looks ok buy a quality gasket from Felpro, Mahle, or Ford clean the surfaces of the head and manifold and reassemble. If the manifold is warped replace it with a better one from Ford, it will rust, but it shouldn't warp or crack. If the surface of the head is uneven clean it thoroughly, focusing on knocking down some of the high spots, and coat your new gasket in Permatex Ultra Copper RTV (81878). This RTV is specifically designed for this use case and works, I've used it on countless vehicles and never had a comeback, nothing else works nearly as well on headers, manifold, turbos, ect. Do not use a substitute product like exhaust muffler or tailpipe sealant, it will not work. Install the manifold on the head and just snug the bolts at first, give the RTV 15 minutes to set up a little before you tighten the bolts all the way.

techrep

iTrader: (1)

You are definitely battling crappy parts... buy an OEM replacement or go with a quality set of shorty stainless steel headers... and Saleen is spot on with his wisdom... plus x2 for the copper, great stuff.

maik

I want to thank you guys so much for helping confirm my suspicions. It's awesome to have a community like this with experts with the knowledge and experience. I've put in an order for a Ford manifold and gasket kit. I also purchased some Copper RTV just so I have everything I might need once I get the old manifold off. Since this is my only vehicle I don't want to leave it out of commission longer than necessary which is why I really appreciate this kind of advice. Thanks again!

techrep

iTrader: (1)

let us know how it turns out..

bhesse

I put Gibson Stainless headers, with SS stud kit and permaflex gaskets, so nice and quiet and possibly some performance increase, TBD
Never want to do this fix again.......

maik

Well there's your my problem right there! I got this swapped out a few weeks ago and finally I'm able to drive around without being too embarrassed again.

Thanks for the advice, everyone!

SALEEN961

iTrader: (1)

That's exactly how the last Dorman exhaust manifold I installed cracked. Wrong material, poor quality control