Exhaust Manifolds | Warped

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

huntergreen

Senior Member
Marine Corps Navy Badge
Joined
Jan 5, 2011
Posts
13,086
Reaction score
28,502
Ram Year
2016
Engine
hemi 5.7
The lowered carbon (graphite) in cast iron these days is a problem. This is why I throw the budget away on brake rotors and spend the bigger bucks on high carbon rotors (graphite). (G3000 min. specs)
Which brand rotors do you use ? Thanks sherm
 

Sherman Bird

Senior Member
Joined
Jun 28, 2019
Posts
3,115
Reaction score
6,774
Location
Houston, Texas
Ram Year
1998
Engine
5.2
I do not trust brands. Instead, I spend the time to do my research. Recently, I did a brake job with rotors on a 2010 Shelby GT500.

Shelby American's price for the "kit" or package was about 3 grand. Knowing that Brembo is the maker of those parts, I found them directly from Brembo for that particular application at roughly half the price of SA.

I did research on other brands, and found that they left out engineering data germane to the carbon content of the rotors and the friction co-efficiency indicator of the pads, and the so-called "pros" had no clue as to my need to know both Graphite (carbon) content AND the 2-letter friction code on the pads .


Inasmuch as this car was/is a race car with license plates, I wasn't given to any form of other than or lesser brake parts.


It was really an eye-opener how ignorant so-called parts pros were during my due diligence in finding the correct parts for this car, keeping in mind that it isn't just a "glorified Mustang" to quote several morons who looked up parts for this car.


The poor-minded "That'll do" mentality which drove those people to think that way is an eye-opening look into "conclusion bias" at it's very worst.


Believe it or not, O'Reilly's came through for me and special ordered the parts for me, but not without me setting an unshakeable boundary as to not settling for "That'll do" parts.
 

Pushrod8Speed

Member
Joined
Nov 15, 2025
Posts
35
Reaction score
41
Location
Texas
Ram Year
2017
Engine
5.7 Hemi
BD Diesel makes great manifolds to solve this problem. The hardware is better also. Makes sure you get the correct ones. Passenger side on DS & DT are not the same. Just replaced mine and yes, they are warped. Previous owner must have replaced them already because the bolts weren't factory and heat shields were missing.
 

Jeepwalker

Senior Member
Joined
Sep 8, 2017
Posts
4,282
Reaction score
5,471
Location
WI
Ram Year
2012 Reg Cab, 4x4
Engine
5.7 Hemi
Guys/Gals,

I put together a PDF today (see attachment below) with pictures how I removed all the broken exh bolts on my tk using the 'Welder Method'. My tk's bolts were broken in the usual locations, which are tricky to get at with a drill. This method has been discussed in detail on the forums many times and there are Y/T videos. Not 100% foolproof but usually a high success rate. All mine were extracted w/o damage to the head. I've used it on other vehicles in the past. A possible option for guys with a welder & steady hand.

Note: I also dropped this in the 'General' forum section ...forgot there was an Exh manifold section.
Note 2: This is NOT a recommendation or suggestion what others should attempt ...but an account of what *I* did. Always have a professional service your vehicle.

Extracted Bolts_Email.jpg

:waytogo:
 

Attachments

  • Broken Exhaust Bolt Removal How-To.pdf
    2.6 MB · Views: 0

Jeepwalker

Senior Member
Joined
Sep 8, 2017
Posts
4,282
Reaction score
5,471
Location
WI
Ram Year
2012 Reg Cab, 4x4
Engine
5.7 Hemi
Here are pictures of what's in the PDF Tech Article (previous post #404) ...below. Pretty self-explanatory. More explanation is in the PDF. Like I say, I'm just throwing this out there of what I did ...not a recommendation of any course of action anyone else should do (covering my butt here), ...or discounting the drill method (which I've also used on vehicles in the past).

20260620_171652.jpg20260620_172214.jpg20260620_172226.jpg20260620_172317.jpg20260620_172428.jpg20260620_172816.jpg20260620_174936.jpg20260620_175126.jpg20260620_162729.jpg20260620_145850.jpg
 
Last edited:

HEMIMANN

Senior Member
Joined
Dec 7, 2020
Posts
9,577
Reaction score
25,200
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Very helpful @Jeepwalker to document all that work. Most people I know around here have done this.

Pretty sure bolt breakage is a 100% surety on Hemi engines. It's just a bad design. I explored long tube headers, but after researching the cost of the parts and install I decided against. I have a heavy duty with the 6.4 Hemi. This engine is sunk lower into the higher frame in the heavy duty and is harder to get at, so I had an indie shop with hoists remove the manifolds. Then got them machined flat and reinstalled. No problems since.

I also explored BD Diesel manifolds, but they lack the EGR port on the left bank. Rick tells me the 6.4 retained EGR for lower combustion temp for engine longevity. But of course the EGR cooler plugs up. How is an engine more "durable" by adding a failure mechanism? *sigh*
 

Jeepwalker

Senior Member
Joined
Sep 8, 2017
Posts
4,282
Reaction score
5,471
Location
WI
Ram Year
2012 Reg Cab, 4x4
Engine
5.7 Hemi
Very helpful @Jeepwalker to document all that work. Most people I know around here have done this.

Thanks. Yeah, I agree ...not new trick. Been doing it long time myself ..lol. Has it's place, doesn't always work. I figured a write-up with pictures and a brief explanation might help some of the newer/younger owners. Perhaps make the process a bit 'clearer'. In addition to drilling which is already described.

I agree... it does seem like warped manifolds are an almost certainty. Probably will continue to be for guys who had brand new ones installed. It's not just a Ram thing but they seem for sure on these Hemi's.

That said, most vehicles have some sort of common 'weakness' that eventually occurs.

:cheers:
 

HEMIMANN

Senior Member
Joined
Dec 7, 2020
Posts
9,577
Reaction score
25,200
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Thanks. Yeah, I agree ...not new trick. Been doing it long time myself ..lol. Has it's place, doesn't always work. I figured a write-up with pictures with a brief explanation might help some of the newer/younger owners. Perhaps make the process a bit 'clearer'.

I agree... it does seem like warped manifolds are an almost certainty. Probably will continue to be for guys who had brand new ones installed. It's not just a Ram thing but they seem for sure on these Hemi's.

That said, most vehicles have some sort of common 'weakness' that eventually occurs.

:cheers:

I don't recall reading from the 5.7 Hemi guys in the Ram 1500 model (5.7 is also available in the Ram 2500 for some reason) that tried BD Diesel manifolds if they worked. i.e. - if they didn't warp and break something after 60k miles.

I've heard Ram's 2nd attempt at manifold design breaks the manifold instead of the bolts. Thermal cycling warpage is a difficult design, but certainty not insurmountable. Requires stiff manifold and strong bolts. But those cost more (wait for it).....money!
 

Sherman Bird

Senior Member
Joined
Jun 28, 2019
Posts
3,115
Reaction score
6,774
Location
Houston, Texas
Ram Year
1998
Engine
5.2
I don't recall reading from the 5.7 Hemi guys in the Ram 1500 model (5.7 is also available in the Ram 2500 for some reason) that tried BD Diesel manifolds if they worked. i.e. - if they didn't warp and break something after 60k miles.

I've heard Ram's 2nd attempt at manifold design breaks the manifold instead of the bolts. Thermal cycling warpage is a difficult design, but certainty not insurmountable. Requires stiff manifold and strong bolts. But those cost more (wait for it).....money!
I find it interesting that we are well into the second hundred years of producing cast iron for heated things from stoves to exhaust manifolds. Obviously, the true problem is what alloy has been deleted.
 

HEMIMANN

Senior Member
Joined
Dec 7, 2020
Posts
9,577
Reaction score
25,200
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
I find it interesting that we are well into the second hundred years of producing cast iron for heated things from stoves to exhaust manifolds. Obviously, the true problem is what alloy has been deleted.

Sherm, educated spit-balling here, but it looks like whoever design Ram's Lincoln logs FEA'd them to survive warranty and no longer (sometimes not even then). There is a serious lack of material in the high stressor zones where bends are. They don't have many sharp edges, so they likely got stress concentration zones correct. Just not enough material for adequate thermal expansion and contraction fatigue cycles not to permanently yield. Of course a high strength alloy would improve life, but there is only so much you can do with cast materials, esp. in high temp zones. It's really a geometry + adequate material problem. Just look at BD Diesels design by comparison.
 

PA Ram

Senior Member
Navy Badge
Joined
Jan 1, 2023
Posts
492
Reaction score
773
Location
Quakertown, PA
Ram Year
2017
Engine
Hemi 5.7
Sherm, educated spit-balling here, but it looks like whoever design Ram's Lincoln logs FEA'd them to survive warranty and no longer (sometimes not even then). There is a serious lack of material in the high stressor zones where bends are. They don't have many sharp edges, so they likely got stress concentration zones correct. Just not enough material for adequate thermal expansion and contraction fatigue cycles not to permanently yield. Of course a high strength alloy would improve life, but there is only so much you can do with cast materials, esp. in high temp zones. It's really a geometry + adequate material problem. Just look at BD Diesels design by comparison.
I'm very happy with my BD Diesel manifolds to date. Not sure the mileage i have since installing them about a year and a half or so ago, but I also tow pretty heavy April through October for camping and have had no issues. I had 2 snapped bolts in the back of both manifolds with one flush on each side and one sticking out enough to grab. The BD manifolds are definitely heavier and have thermal expansion sleeves to keep bolts from snapping.
 

Sherman Bird

Senior Member
Joined
Jun 28, 2019
Posts
3,115
Reaction score
6,774
Location
Houston, Texas
Ram Year
1998
Engine
5.2
Sherm, educated spit-balling here, but it looks like whoever design Ram's Lincoln logs FEA'd them to survive warranty and no longer (sometimes not even then). There is a serious lack of material in the high stressor zones where bends are. They don't have many sharp edges, so they likely got stress concentration zones correct. Just not enough material for adequate thermal expansion and contraction fatigue cycles not to permanently yield. Of course a high strength alloy would improve life, but there is only so much you can do with cast materials, esp. in high temp zones. It's really a geometry + adequate material problem. Just look at BD Diesels design by comparison.
My old 2007 KIA Sorento, with the 3.8L V-6, had stout braces on the exhaust pipes that relieved the weight of the Y-pipe and cats from the manifolds to the engine block. 271,000 miles at the time I sold it, and those equally thin manifolds had never, ever had any issues, including after I replaced the engine. The newer and different generation 2014 KIA Sorento of my wife's has no such braces. But, the newer vehicle is FWD, as opposed to the RWD config of the 2007. (first gen.)
 

HEMIMANN

Senior Member
Joined
Dec 7, 2020
Posts
9,577
Reaction score
25,200
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
My old 2007 KIA Sorento, with the 3.8L V-6, had stout braces on the exhaust pipes that relieved the weight of the Y-pipe and cats from the manifolds to the engine block. 271,000 miles at the time I sold it, and those equally thin manifolds had never, ever had any issues, including after I replaced the engine. The newer and different generation 2014 KIA Sorento of my wife's has no such braces. But, the newer vehicle is FWD, as opposed to the RWD config of the 2007. (first gen.)
Stout braces = extra material
 

crackerjack1957

Senior Member
Joined
Sep 26, 2015
Posts
2,376
Reaction score
3,305
Ram Year
2014 Sport 1500 CC 4x4
Engine
Hemi 5.7...65RFE...4.56
I find it interesting that we are well into the second hundred years of producing cast iron for heated things from stoves to exhaust manifolds. Obviously, the true problem is what alloy has been deleted.
I would definitely agree on the alloy composition......If we do prototype work and can't wait for the alloyed material like 8620.
Our parts will warp after machining from stress of the material removed.
 

Grams

Senior Member
Joined
Oct 4, 2024
Posts
1,123
Reaction score
1,830
Location
Texas
Ram Year
2024 & 2015
Engine
6.7 Cummins & 5.7 Hemi
The Pax-side manifold on my 2015 5.7 Hemi broke it’s rear-most bolts.

My favorite shop replaced the manifold with a “Dorman Kit” which includes new manifold, bolts and heat-shield. They assure me they’ve done many of these and the Dorman Kit is what they’ve had great success with.
 
Last edited:

PA Ram

Senior Member
Navy Badge
Joined
Jan 1, 2023
Posts
492
Reaction score
773
Location
Quakertown, PA
Ram Year
2017
Engine
Hemi 5.7
The Pax-side manifold on my 2015 5.7 Hemi broke it’s rear-most bolts.

My favorite shop replaced the manifold with a “Dorman Kit” which includes new manifold, bolts and heat-shield. They assure me they’ve done many of these and the Dorman Kit is what they’ve had great success with.
I've had good luck with Dorman parts. Replaced my lower intermediate steering joint with a Dorman this year (April I think) and it works like new. Was relatively easy to replace even though I was doing it as it got dark. Bought a few other parts over the years and never had an issue.
 

Burla

Senior Member
Joined
Apr 28, 2012
Posts
27,667
Reaction score
58,019
Ram Year
2010 Hemi Reg Cab 4x4
Engine
Hemi
The rumor is the new hemi's have addressed this. Maybe old hemi's can get these "new bolts"? I have my doubts, if they really wanted to fix this add material to manifolds like older styles that never had this issue.

 
Back
Top