Exhaust Manifolds | Warped

[Fast69Mopar]

Well you would think it would be noisy & misfiring but I have seen some pictures of cams on here that looks like they have run it for several months with the lifters not working properly. Damn near rounded the lobes off. I would think after just a few thousands were taken off the lobes you would start getting misfires.

There have been alot of owners who mistake the lifter noise for the exhaust leak and the longer it goes the more damage is done.

I have been able to catch a few that have had seized rollers and just scarred the camshaft lobes but most just wipe out a love and it's game over.

 

[Fast69Mopar]

Wow... sounds like some flunky that got fired from Wal Mart Tire & Lube was working on it. To have to have that done to every hole somebody REALLY didn't know what they were doing. As others have done, they would have been better off buying headers & all new bolts & been done with it. Sounds like they changed bolts more often than they changed oil!

Man I know. I almost decided to toss the heads under the bench and use a fully prepped set I have waiting for a customers project but I changed my mind and repaired them.

I used a CNC to drill the holes and then installed the Heli-Coils. Now the truck has a completely different motor in it since my customer changed his mind from a healthy 5.7 to an even healthier 6.1

I made a trade to get the 5.7 and cut a deal on building the 6.1 and installing a 4-link in the truck. Not a bad trade.

 

[Justin33]

Ok a meter reading this thread I’ll ask you guys your take. I feel like I get tick on startup, keep in mine I live in Maine so colder temps. I’ve asked them to look at the manifold bolts at least once and they said they were fine at dealership so does that mean I need to ask again as my five year 100k will end in May. I also have a squeal at 2k rpm that I have asked them to address multiple times and they say they can’t replicate it. No **** guys it doesn’t do it idiling engine needs to be under load.

also it’s a 2015 with 15k that I like to lead foot.

 

[Ox1500Sport]

So, if one opted to buy "new" MOPAR manifolds, has the manufacturing issue been corrected? Or, is resurfacing the only way to go?

 

[Wild one]

So, if one opted to buy "new" MOPAR manifolds, has the manufacturing issue been corrected? Or, is resurfacing the only way to go?

They need to be heat cycled several times,so re surfacing new ones won't really accomplish much,as they haven't taken a set yet

 

[Fast69Mopar]

They need to be heat cycled several times,so re surfacing new ones won't really accomplish much,as they haven't taken a set yet

@Wild one is correct, they need several heat cycles before milling or belt sanding will accomplish anything. They all look great out of the box and their flatness is almost always withing the .001"-.003" range.

If you were to purchase new manifolds I would say to run them 20,000 miles in all types of driving conditions before removing them for milling.

 

[Ox1500Sport]

They need to be heat cycled several times,so re surfacing new ones won't really accomplish much,as they haven't taken a set yet

No guys, I'm asking:

1) Has the manufacturing defect been corrected, so new MOPAR manifolds are no longer expected to warp

or

2) Is resurfacing the old manifolds the only way to go

 

[crackerjack1957]

#2........no guarantees on #1

 

[Wild one]

No guys, I'm asking:

1) Has the manufacturing defect been corrected, so new MOPAR manifolds are no longer expected to warp

or

2) Is resurfacing the old manifolds the only way to go

It's not really what i'd call a manufacturing defect,cast iron warps pretty easily,and needs several heat cycles before it takes a set.Warped cast iron exhaust manifolds have been an issue with V-8's pretty well since they started making cast iron exhaust manifolds.GM's LS's are also famous for breaking manifold bolts,and as far back as I can remember which is going back to the late 60's /early 70's cast iron manifolds were famous for warping,the worst of them back then were the old FE 360/390 Fords,they'd warp so bad the manifold would actually crack.My dad had a sideline business back then where he'd braze the cracked Ford manifolds,and re-surface them,and he was fairly busy,lol

 

[parker1825]

Well my '09 5.7 right side exhaust manifold, with 126K miles has been leaking for awhile.
On the last gas fill my mileage dropped from ~16mpg to 6.6mpg! My Mac scanner won't
communicate with the ECU so I took it to a local shop and they verified what you can see,
the two rear bolts sheared off and hanging on the heat shield. they quoted me $600, so
I stopped by the Ram Stealers who quoted $1 killabuck per side! Does anyone out there
know a reputable shop, in the San Diego, CA area that are successful with this repair,
without pulling the head? In my old machinist days, we would weld a nut and back the
broken bolt out, but that was on the bench.

 

[crackerjack1957]

Welding nut on is the best option unless of course it is broken flush with head.

 

[parker1825]

Yep, broken off flush. Youtube has a good segment wherein the mechanic actually
welds nuts on flush broken bolts in the vehicle. Like I said, I've done the same on
broken bolts in aluminum, but on the bench some 20 years ago with a tig and much
better eyes.

 

[Dodge 1500 4X4]

Wow guys allot of info here on these ex manifolds, I don't think it was mentioned you don't want to put a harder grade bolt say grade 8 it being so hard they will pull the threads out of the head, I use to run a repair shop out of my home for about 20 years and have seen allot of problems, always had the exhaust manifolds Machined, But I never worked on a Foreign car or rarely for a favor!!

 

[OCDTech]

Yep, broken off flush. Youtube has a good segment wherein the mechanic actually
welds nuts on flush broken bolts in the vehicle. Like I said, I've done the same on
broken bolts in aluminum, but on the bench some 20 years ago with a tig and much
better eyes.

Good call sir. SMA guy is a beast.

 

[OCDTech]

Welding nut on is the best option unless of course it is broken flush with head.

skip to 13:20

 

[parker1825]

Yes, I've seen that video and passed it on to my local shop that had the truck for
three days. Finally extracted the second rear bolt and had to install a TimeSert.
Three days and $600 and I'm back on the road. Kinda makes me want to get a
Toyota next time.

 

[scott lass 18]

I'm well-aware that the 5.7L HEMI has a fairly common issue surrounding the exhaust manifold bolts, causing the "HEMI tick". About 10 days ago, I noticed my truck had a tapping noise when cold-started. I assumed that this was the infamous HEMI tick and honestly didn't give it much thought. It then started to get noticeably and progressively louder and more intense with each day. And where it would normally disappear after the engine warmed up, it's only getting softer, but not going away.

As of today, we are well beyond the "tick" stage. When started cold the noise sounds like a spoon being hammered around the inside of an empty coffee can. A very DEEP and very LOUD, TAP TAP TAP TAP TAP. There is no check engine or malfunction indicator lights, and operationally the truck appears to be driving perfectly fine. No discernible misfires, surging, loping or stalling. Power is always there. Oil level is fine, it runs Mobil1 Fully-Synethic 5W-20 and the oil doesn't appear out of sorts or discolored.

I took it into my local dealer to have them examine the truck and after about an hour and a half they came back with the news that both exhaust manifolds are "warped" and have got to be replaced. When I asked if the truck had a bad lifter, they said that upon initial inspection, their tests showed that all the lifters are operational and moving as they should but, they wouldn't know for sure until the vehicle is dismantled. They said that the exhaust manifold bolts would be replaced along with the manifolds themselves.

My question is, without being a knowledgeable mechanic, even I know that a lifter failure can cost you an engine with almost no effort. This is forcing me to put a huge amount of trust in the shop when they say nothing is wrong with the lifters and that it is merely the manifolds.

I would love to know what you all would do here. Unfortunately, my living situation and job do not afford me the ability to dismantle the truck myself and given the time of year and the fact that my only other vehicle is a Harley... having the truck down for a couple weeks torn apart isn't an option either.

Your input is appreciated. Thanks all!

hi yes mine was a injector and one exhaust ,manifold was really warped its lest noise but still hear noise guess we have to drive and see how it goes 59,300 on truck oh well ! oh one bolt was broken completely off at head so sure glad have my powertrain warranty ! at 10 years old lucky to get it done 100.00 all the things they did and some things without asking mad about that !

 

[NETim]

I've scheduled my rig to get the broken exhaust studs replaced with the mechanic here in my little town of 350. I've done business with him for decades and trust him w/o question.

I have a warranty on the truck, so it's not going to be too painful.

HOWEVER, he's not a fan of milling down the warped manifold. He says the studs will break again anyway. Same as if I were to go with shorty headers.

I hate to butt heads with him 'cause he's a good guy and a great knowledgeable, experienced mechanic.

 

[Scottyshortbus]

Looking for a recommendation for new manifold bolts/studs for use with stock manifolds and heat shields. I’ve already removed the 4 broken bolts and had the stock manifolds milled down, just looking for some quality bolts to put things back together.

 

[tidefan1967]

Looking for a recommendation for new manifold bolts/studs for use with stock manifolds and heat shields. I’ve already removed the 4 broken bolts and had the stock manifolds milled down, just looking for some quality bolts to put things back together.

ARP grade 8