Exhaust manifolds

[Donaldgram5.7]

Anyone else having issues on getting manifolds in to have them replaced? It's been over 4 months waiting for them on my 2020 1500 5.7. Dang truck sounds awful when first started and now I'm smelling exhaust fumes in the cab while driving. Thanks!!

 

[BoxerguyT89]

I take my truck in next week for diagnosis on what I assume is a cracked manifold. Sounds like I might be in for a wait.

 

[Maxum]

I take my truck in next week for diagnosis on what I assume is a cracked manifold. Sounds like I might be in for a wait.

Same here…could be months. I have two cracked.

 

[Geddyflea]

I just got mine back from the dealer this morning. It took 9 weeks from the time they found it. Not their fault at all and they did everything in their power to make me happy. I can't recommend North Knoxville CJDR more.

 

[kdoublep]

That's crazy. I couldn't wait. I'd have to get shorties. My truck is an essential item.

 

[Geddyflea]

That's crazy. I couldn't wait. I'd have to get shorties. My truck is an essential item.

I didn't make that very clear. They found the cracked exhaust manifolds and ordered them 9 weeks ago. They got the parts in last week. I took the truck in last Wednesday for them to fix it and got it back today. They only had it for 2 1/2 days.

 

[kdoublep]

That's much more encouraging.

 

[My1stHemi]

I had the factory manifolds crack on my truck maybe two years ago. Dealer denied there was a problem so I installed shorties from AFE. I have had a nightmare with them from day one. Multiple failed welds that cracked warped flanges, out of round collectors. Leaks leaks and more leaks. I can tell you that removing the factory manifolds are a breeze. Shorty headers are a son of a b. I’ve had mine on and off 4 times. I even had them jet hot coated and that failed too.
The collectors just stated leaking again on cold starts. With no gasket, I’m giving up. As soon as the OEM manifolds are available I’m going back to stock.

 

[MikeyHo808]

Already had my passenger side replaced. That instance, in and out in under a week, parts on island, no problem.
Now, I’m not so sure. Mines goes in Tuesday for the diagnosis, but that sound is so distinct, I just can’t tell which side. I think it’s my drivers side now, but I thought it was the last time so we’ll see. What’s the odds of me cracking the same side?

 

[6of36]

I had the factory manifolds crack on my truck maybe two years ago. Dealer denied there was a problem so I installed shorties from AFE. I have had a nightmare with them from day one. Multiple failed welds that cracked warped flanges, out of round collectors. Leaks leaks and more leaks. I can tell you that removing the factory manifolds are a breeze. Shorty headers are a son of a b. I’ve had mine on and off 4 times. I even had them jet hot coated and that failed too.
The collectors just stated leaking again on cold starts. With no gasket, I’m giving up. As soon as the OEM manifolds are available I’m going back to stock.

Since you are buying them, I would hit a junkyard.

 

[6of36]

Already had my passenger side replaced. That instance, in and out in under a week, parts on island, no problem.
Now, I’m not so sure. Mines goes in Tuesday for the diagnosis, but that sound is so distinct, I just can’t tell which side. I think it’s my drivers side now, but I thought it was the last time so we’ll see. What’s the odds of me cracking the same side?

They were replaced with the same part. Two manifolds, 50/50 the same one.

 

[Cbty2050]

Since you are buying them, I would hit a junkyard.

Buy used manifolds? The kits with all gaskets and hardware are around $100/side. They have a warranty on them.

 

[Maxum]

Buy used manifolds? The kits with all gaskets and hardware are around $100/side. They have a warranty on them.

Problem I think is, that new ones will warp and crack eventually as well, but if you had a set that was used and not cracked yet, you could sand the surface flat and use them, essentially solving the issue, because they have already warped, but resurfaced, so heat won’t warp them any further.

 

[BowDown]

Problem I think is, that new ones will warp and crack eventually as well, but if you had a set that was used and not cracked yet, you could sand the surface flat and use them, essentially solving the issue, because they have already warped, but resurfaced, so heat won’t warp them any further.

I don't think warping is a big issue which seems to be cracking after x number of heat cycles. Cast iron exhaust manifolds tend to crack more than warp, warping (the exhaust port flanges) is typically a header problem so you could by a used $25 manifold and have it crack on immediately or in 100k miles

 

[Maxum]

I don't think warping is a big issue which seems to be cracking after x number of heat cycles. Cast iron exhaust manifolds tend to crack more than warp, warping (the exhaust port flanges) is typically a header problem so you could by a used $25 manifold and have it crack on immediately or in 100k miles

Possibly, all I know is that garage explained to me that the heating cycles warp them and that causes the bolts to break and in some cases, crack the manifolds if they warp enough. Both mine are cracked and been cracked for a while, I figure started with just over 30k kms on the truck. If they replace with identical parts, I expect the same problem again in another 30k kms, which is crazy. I know people who have sanded older ones and have had them in for 60k kms so far and no issues. Might just be luck, no idea

 

[6of36]

Buy used manifolds? The kits with all gaskets and hardware are around $100/side. They have a warranty on them.

I'm surprised they are that cheap, but yeah, if they are not any better than what you are replacing, I would go to a junk yard, and probably pay $10 or 15 for them, and save the money. I just looked at local yard listing, $20.

 

[Cbty2050]

I'm surprised they are that cheap, but yeah, if they are not any better than what you are replacing, I would go to a junk yard, and probably pay $10 or 15 for them, and save the money. I just looked at local yard listing, $20.

You can actually find the kit online for under $70. That's gasket, all nuts, bolts, studs, and heat shield.

 

[Maxum]

You can actually find the kit online for under $70. That's gasket, all nuts, bolts, studs, and heat shield.

But it’s a new set, which will warp again. A used set is already gone through hundreds of heating/cooling cycles and is already done warping. If you flatten that surface, you have a set that should last quite a ehile

 

[BowDown]

But it’s a new set, which will warp again. A used set is already gone through hundreds of heating/cooling cycles and is already done warping. If you flatten that surface, you have a set that should last quite a ehile

Wouldn't the now "used" sets already installed that are failing be the same? Just because a junkyard set hasn't cracked doesn't mean it wont.
Mine didn't fail until ~40k miles, thousands of heat cycles during that time. Now, if you found a high mileage (100k+ miles) set that hadn't cracked, I'd agree with you

 

[wegasque]

I just got mine back from the dealer this morning. It took 9 weeks from the time they found it. Not their fault at all and they did everything in their power to make me happy. I can't recommend North Knoxville CJDR more.

Thanks. I'll keep them in mind after I move.