Cracked Exhaust Manifold

[Nick@GotExhaust]

Hey everyone, pretty sure my 2019 5th gen is joining the manifold club. I have a noticeable exhaust tick on the passenger side when cold, disappears above idle RPM. I'm going to tear into it later this week to inspect but had a couple questions I'm hoping everyone can answer for me.

1) With the BD manifolds listed here can you just swap 1 bank at a time? Just curious if the interior chambers are different volume than stock and if swapping just 1 would cause me problems in exhaust balance. If my drivers side manifold isn't cracked (yet) I don't want to spend the money on a new mani for it yet.

2) I know 4th gens broke bolts just from expansion\contraction or whatever causes it. But has anyone who has replaced 5th gen manifolds run into bolts snapping off while trying to remove them? Tbh the job doesn't look that bad...unless bolts start snapping off. I'm really hoping to not have to find a way to drill in and use an ez-out in that space, not sure I'll fit well enough to trust my drill to run straight. I know I always hear rumors of exhaust manifolds snapping off bolts when worked on, but I'm hoping mine only being 5 or so years old may have better luck...

3) The tick isn't huge right now, but noticeable at idle. Am I going to hurt anything driving on it the way it is for now until I can have a look? I don't imagine it's losing a TON of exhaust backpressure as is so I don't see it severely leaning out one cylinder, but not positive on this assumption. Obviously is this was a 2 stroke, different story.

My plan at this point is to go in through the wheel well and try to see if the tick\leak is at the manifold or the flare\donut connection. If it is the manifold I was thinking I would at least try turning each bolt 1 turn and if none snap off I'll order a new part. If even 1 snaps off odds are I'll limp it to a shop and pay the price. I'm not the worst with snapped bolt extractors, but drilling in around the aluminum head makes me nervous.

1) flow is pretty much the same. The BD ones do not offer any performance improvement just a more durable design than OEM.

2) the 4th gen had manifolds warping causing the bolts to snap before even trying to remove them in many cases. 5th gens seem to just crack the manifold and not warp them and snap the bolts, mainly due to the added bracing. Any manifold swap has the potential of having a snapped bolt during removal. My advice is soak them in penetrating oil the night before, then hit them again before you start removal. Then just take it slow and keep even pressure. Not all removals are the same, miles, age, climate the truck is in during its lift, etc...all play factors. I would have an EZ out kit on hand just in case but many people are able to remove them without snapping them

3)a basic tick from a manifold leak wont hurt it but I would start getting your gameplan together to replace them sooner than later.


Message me if you are interested in a quote on BD manifolds, shorty headers, or long tubes

 

[Guyfromthenorth]

I went ahead and got a fluxcore wire feed welder in case I snap some bolts off, I have a TIG in my shop but it won't reach and isn't exactly the best option for welding nuts on shanks. I still have my reverse drill bits, easy outs, etc too. Just a quick tip for anyone shopping for parts, I called the dealer for their manifold kit price then called NAPA. Believe it or not NAPA was 200$ more than the dealer price. I went with the dealer in the end for the parts, it comes with everything except the "X Bar" that the 5th gen has that stopped the snapping bolts (but lead to cracking manifolds). They said the X bar is usuall re-usuable that's why it's not included.

Whenever I find time to attempt this repair I'll post here what happened.

 

[Slinge]

Hopefully you won't snap any bolts.
I remember a member here telling someone that bolts don't usually snap....that they often come out easily !

 

[Guyfromthenorth]

Hopefully you won't snap any bolts.
I remember a member here telling someone that bolts don't usually snap....that they often come out easily !

That's the energy I need these days lol. The truck is only 5yr~ old, but it's a dice roll on bolts it seems. Even the brake rotors needed the set screws drilled and extracted, and the rotors needed ALOT of persuasion with the back-bolt trick, penetrating oil, a hammer, and a torch. Rust somehow destroys metal making it as tough as a soup cracker, but somehow is also the strongest weld in the universe...