Hemi Exhaust Manifold New Design?

[HEMIMANN]

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]

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.

 

[HEMIMANN]

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]

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?

 

[HEMIMANN]

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.

 

[PoMansRam]

Are the exhaust manifolds different between the 6.4 and 5.7?

The only "update" I've seen to the 5.7's manifolds were the addition of tie bars in ~2018-19+

 

[HEMIMANN]

The manifold outlets are the same. I think we saw the same machined part number for both at one time.
I know the 6.4 truck engine has sodium filled valves the 5.7 does not.

 

[DILLIGAF]

Polishing a **** isnt an improvement.

 

[HEMIMANN]

Seeing as we're not getting what we want, imma keep on polishing!

 

[David H]

What was the quote?