Hemi Exhaust Manifold New Design?

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HEMIMANN

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I decided @ 47,000 miles I'd better get my 2017 Ram 2500 with 6.4 Hemi exhaust manifolds machined before they leak and break bolts. Seems like a 100% fail rate for Forum Members.

Today I called up our local expert Tim's Custom Exhaust in Minneapolis - he knows all about it, says they do "4 or 5 every WEEK" (!) - BUT - he says FCA came out with a redesigned exhaust manifold that doesn't warp, he's had no returns, and machine shops around town don't want custom work anymore like they did back in the day.

So, I set up an appointment @ Tim's next week for new logs and Remflex gaskets. I'll report to members anything more I find out. I decided against long tube headers due to expense, even though you get ~ +10% more torque, because the high flow cats aren't EPA certified.
 

Burn2k12Ram

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I decided @ 47,000 miles I'd better get my 2017 Ram 2500 with 6.4 Hemi exhaust manifolds machined before they leak and break bolts. Seems like a 100% fail rate for Forum Members.

Today I called up our local expert Tim's Custom Exhaust in Minneapolis - he knows all about it, says they do "4 or 5 every WEEK" (!) - BUT - he says FCA came out with a redesigned exhaust manifold that doesn't warp, he's had no returns, and machine shops around town don't want custom work anymore like they did back in the day.

So, I set up an appointment @ Tim's next week for new logs and Remflex gaskets. I'll report to members anything more I find out. I decided against long tube headers due to expense, even though you get ~ +10% more torque, because the high flow cats aren't EPA certified.
They must of finally learned what heat cycled is lol. Good for them though. No doubt let us know and try and get a close up pic of one if you could.
 
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HEMIMANN

HEMIMANN

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They must of finally learned what heat cycled is lol. Good for them though. No doubt let us know and try and get a close up pic of one if you could.

If it's 100% fail, or at least a high failure rate, I'd wager they've burned through quite a bit of warranty cash by now, yes? The parts themselves aren't that expensive - just cast iron logs with a little machining made by the millions, but labor to replace x 2 per vehicle? Must be astronomical.

Also interesting is they've done only a couple of bandaid attempts at improving valve lifter roller and cam failures. The percentage failure are likely much lower, but the expensive to replace is massive.

I remember we did the math to decide which to warrant, and which to re-design.
 

Burn2k12Ram

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If it's 100% fail, or at least a high failure rate, I'd wager they've burned through quite a bit of warranty cash by now, yes? The parts themselves aren't that expensive - just cast iron logs with a little machining made by the millions, but labor to replace x 2 per vehicle? Must be astronomical.

Also interesting is they've done only a couple of bandaid attempts at improving valve lifter roller and cam failures. The percentage failure are likely much lower, but the expensive to replace is massive.

I remember we did the math to decide which to warrant, and which to re-design.
For the lifters I know they attempted larger needle bearings, did that actually reduce failures at all? Wish there was hard numbers showing failures for which specific lifters. How many different lifters did they use for these gen3's?
 
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HEMIMANN

HEMIMANN

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For the lifters I know they attempted larger needle bearings, did that actually reduce failures at all? Wish there was hard numbers showing failures for which specific lifters. How many different lifters did they use for these gen3's?

I've never seen any data or insider info about the supposed re-sourcing and redesign of the lifters, that supposedly began with model year 2017. I've seen Forum Members with failed lifters with these later model years.

That's all the data I know. Stellantis has all that data, of course. Too bad we don't have an insider or ex-insider to spill some of it to us.
 

ColesRAM

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Interested, so please keep us updated. Thanks.
 
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HEMIMANN

HEMIMANN

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If they’re anything like the new manifolds on the 5th gen trucks they just crack in addition to warping and breaking the bolts. I would still just plane the old ones and reuse if I wasn’t going to headers.

1. Re-read my post...the guy's been in the custom exhaust biz for 30+ years and says the custom one-off machine shops have gone away in my area.

2. He's been in the biz long enough to know if something should be recommended to his customers or not. I'd trust him before a lot of other bloggers.
 

tidefan1967

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1. Re-read my post...the guy's been in the custom exhaust biz for 30+ years and says the custom one-off machine shops have gone away in my area.

2. He's been in the biz long enough to know if something should be recommended to his customers or not. I'd trust him before a lot of other bloggers.
Honestly I would be more compelled to believe the regulars on here(they know who they are) unless you know the guy personally. I haven’t seen too many muffler shops over the years that I was impressed with. I guess I’ve seen one too many trucks running around over the years with muffler shop dual exhaust’s with one tail pipe dragging the ground. Best of luck!
 
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HEMIMANN

HEMIMANN

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Honestly I would be more compelled to believe the regulars on here(they know who they are) unless you know the guy personally. I haven’t seen too many muffler shops over the years that I was impressed with. I guess I’ve seen one too many trucks running around over the years with muffler shop dual exhaust’s with one tail pipe dragging the ground. Best of luck!

Yep. This guy's vetted - I know a number of guys around here who've had work done there and he's done great for them, plus his online independent reviews are top notch. I hear what you're saying about Joe Blow muffler shops - this guy's not that.......been here for decades, has 8 lifts, etc.
 

tidefan1967

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Yep. This guy's vetted - I know a number of guys around here who've had work done there and he's done great for them, plus his online independent reviews are top notch. I hear what you're saying about Joe Blow muffler shops - this guy's not that.......been here for decades, has 8 lifts, etc.
Glad to hear it. Good muffler shops are hard to find!
 

Wild one

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1. Re-read my post...the guy's been in the custom exhaust biz for 30+ years and says the custom one-off machine shops have gone away in my area.

2. He's been in the biz long enough to know if something should be recommended to his customers or not. I'd trust him before a lot of other bloggers.
Get the old manifolds back,lay a straight edge across them,if they're bad,buy yourself a decent sized belt sander and go to work on them with 50 grit,then finish them up with 80 grit,and throw them in storage for when the "new design" breaks,lol
 
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