More 2012 F150 3.5l Exhaust leaks

markoney1955 · Nov 27, 2022

I have a 2012 Ford F150 Lariat with the 3.5L turbo. I had the rear stud on the passenger’s side exhaust manifold break as so many others have. I replaced the exhaust manifold, gasket and mounting hardware. Seem to fix the problem. A few weeks later the driver’s side had the same problem. Same fix all is good. A month or so after fixing the passenger’s side I start hearing another leak. I check and all bolts are intact. A few weeks later and now the drivers side is having a similar leak. Question is what did I miss and what do I do to fix it? When I reinstalled the manifolds, I tried to tighten all hardware to spec. I feel Like I got it all tight enough but maybe not. Should I have new gaskets before I tear into it again or just try to re-tighten everything. Looks like I will have to pull the turbos either way.

Thanks,
Mark

Evo8John · Nov 28, 2022

Did you do the updated manifolds?

markoney1955 · Nov 28, 2022

I ordered stock Dorman replacements with gaskets online.

Evo8John · Nov 29, 2022

Ford recently released a new cast stainless manifold to replace the original design which utilizes more of the available bolt holes and spreads the load out better to prevent warping.

If you do find that the Dorman manifolds have warped I would suggest replacing them with the updated Ford design.

markoney1955 · Nov 29, 2022

Thanks for the feedback. I plan on working on it right after Christmas. I'll see what I see.

mass-hole · Nov 29, 2022

See here for the updated designs.

New OE 2011-2016 Manifolds

Not sure if this should go here or the problems section. BL3Z-9430-D BL3Z-9431-D I just got mine in the mail so I figured I would post up some pictures. Passenger side in the foreground, notice how whacky the flange is around the rear port: Drivers Side up: Passenger: Driver:

www.f150ecoboost.net

More 2012 F150 3.5l Exhaust leaks

New OE 2011-2016 Manifolds

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