is what i heard from a cummins guy tonite at work. He was talking about the superiority of the cummins, and kept saying one of the biggest problems with heavily modding a duramax are the aluminum heads and their prone to crack. Any truth to this? or BS? What are your thoughts on this?

I run stock but think that if there were big issues with AL heads it would have been addressed already.

Take a poll, you can do it here, and see out of the 650,000 DMax's produced have had craked heads.

tell him to do a search on dodge tranny's!

I think the only "cracked" head may be on your friends shoulders!! LOL

Pure BS. Aluminum heads are nothing new. Ford's been using them since 1990 or so on the 4.6L's, which have basically zero head problems. If anything, the Al heads HELP becasue they can disperse the heat faster than Fe heads.

Tell him the facts don't back up his assertion. GM has been building Duramaxs with aluminum heads for 5 years now... if there was a problem with the heads it would have reared itself by now, because there's certainly not a shortage of heavily modded Duramaxs out there.

Also, here's a direct quote from the Duramax FAQs at The Diesel Page's website:

Q: Is there any truth to the rumors we're hearing about aluminum cylinder head and head gasket failures?

A: No, there is absolutely no truth to the plethora of head/gasket rumors that have circulated these past few years. There have been a few coolant leaks that developed because a leaking head gasket, but no head gasket has failed because of the aluminum heads. In fact, we believe the aluminum cylinder heads are the primary contributing factor in why the Duramax 6600 has become so successful and has developed a very good reliability record.

The guy is a Cummins man... that's fine, the Cummins is a fine engine... but it looks like he's just looking for an excuse to bag on the Duramax. If he really knew what he was talking about he'd have brought up the fuel injector problems or the overheating problems some have experienced... but instead he takes a shot in the dark at the aluminum heads with now real basis in fact (or facts about actual heads cracking) to back him up. :blahblah:

ever tried to crack aluminum well i would say very hard to do. thats why we use aluminum heads on the race cars that we buildbecause they take the beating and can be repaired if damaged. now cast iron will crack very easy drop a cast iron head see what happens. so tell your friend he should of bought a duramax lol

I did hear that Ford was having problems with the aluminum heads on the V-10 Triton engines. I understand that they use a threaded insert for the spark plugs, and over time these inserts work their way loose. Maybe the Cummins guy heard about Ford's problems, and figured that ALL engines with aluminum heads must be having problems.

Joseph

almost 99% of the cars on the road now have aluminum heads now also aluminum blocks so i think if aluminum had problems then they wouldn't be useing it so much

my chevy vega, back in the day, had an aluminum block and cast iron head.....I think!

Back in the day I had an Olds with a quad 4, talk about issues. The big thing with using dissimilar metals is the expansion/contraction rate. Al. moves a whole lot more than cast iron. But GM has engineers that get paid to make a good product. There is also a warranty for things like that.

is what i heard from a cummins guy tonite at work. He was talking about the superiority of the cummins, and kept saying one of the biggest problems with heavily modding a duramax are the aluminum heads and their prone to crack. Any truth to this? or BS? What are your thoughts on this?

All I have to say is 100% of the top fuel dragsters run aluminum heads, if they are good enough to take the stress of the most powerful engines in the world then they are good enough for me.

Ask him about that.

.

Volkswagon has been using aluminum heads on their Diesels for many years without problems. Indy cars run Aluminum heads with 60+ pounds of boost. The fact that ANY engine is less reliable, or can't produce big power because it has aluminum heads is pure BS.

The old stories about problems with aluminum heads originated in the sixties ( about the time Sweden :eek: designed what is now the Cummins engine). Those first aluminum heads did give problems, but, like fuel injection and ignition systems, things have vastly improved. Aluminum heads are state of the art - cast iron is yesterdays news.

2004.5 2500HD LLY/A CC SB

is what i heard from a cummins guy tonite at work. He was talking about the superiority of the cummins, and kept saying one of the biggest problems with heavily modding a duramax are the aluminum heads and their prone to crack. Any truth to this? or BS? What are your thoughts on this?

Come on....You've been here over a year now....How many threads have you seen that start with "Oh no, my cylinder head craked...." One?? Two maybe??
A site like this will show the worst in a truck (if you need any proof of that, just do a search on overheating.........and if you plan to read them all I hope you're in a very comfortable chair)
No matter who you talk to, if they have any interest in trucks, will spread some rumor about an engine or drivetrain. "My buddy had one of those and the pos has been in the shop X amount of times in the last three months :blahblah: .... and on and on and on.....usually the statement is ended with...."I'm sure glad I own (insert brand of truck here) instead of (insert brand of truck his buddy has)"
Take it for what it's worth.....words....and they are very cheap in this day and age..

Your coworker is not schooled on the Duramax. Let him know that you don't appreciate him throwing out "facts" that he has never proved or researched. It makes him sound ignorant and stupid. I would never believe another word this guy says.

Many racing engines have aluminum heads, lots of power and heat, no real problems that I am aware of. In fact my son that races just bought a set.....they aren't cheap though.

):h If you poke around the CTD performance sites you'll find that THEY'RE the ones who need to reinfoce the cylinder heads to run higher boost pressures (head studs, o-ring jobs, etc., etc.). You might also remind him that in the 04.5 CTD they switched to pistons made out of -- you guessed it -- aluminum. The real "weak point" when you start adding mods, if that's what he wants to talk about, is the transmission. This is true of all the diesel pickup manufacturers, although some perhaps more than others.

When the Duramax first came out, many people were skeptical about the use of aluminum for the heads. I remember I heard that too back then. I myself wondered about it. But after several years on the market and millions of miles, they have proven to be a very reliable design. I think you're buddy has probably never gotten over that initial skepticism and has accepted it as fact. That's how urban legends get started.

I know I read somewhere on this site that the difference in thermal expansion rates between aluminum and cast iron is what helps the dmax keep it's gasket seal, especially when mod'ed...

I did hear that Ford was having problems with the aluminum heads on the V-10 Triton engines. I understand that they use a threaded insert for the spark plugs, and over time these inserts work their way loose. Maybe the Cummins guy heard about Ford's problems, and figured that ALL engines with aluminum heads must be having problems.

Joseph

125,000 on a V10 Ford with no issues.

If you're stupid and overheat your engine, aluminum heads are more likely to crack than iron, other than that.. :blahblah:

Its true Ford is having problems with their AL heads, however its not for cracks, blown head gaskets or such. The problem is Ford didn't think far enough ahead to put Cam Bearings in those Al heads. Yep, they are running those cams right on Aluminum. Which is fine as long as you have a nice steady flow of oil. something happens to the oil, well... things aren't so fine and dandy at that point. This is the main reason Ford is replacing so many heads on their Modular motors.

my chevy vega, back in the day, had an aluminum block and cast iron head.....I think! Yer right because I had one, 1976, 4 speed, yellow in color.:ro) :ro)

one of the first main stream manufators to put on al heads was honda and being dissimalar metals the expand and contract and different rates so the once lowly civic had problems with head gaskets. so why al. it stays cooler alowing the fuel charge to remain dense more power. it is lighter but the main reason is the temp reduc. so anyway the problem was solved a long time ago with better gasket materials. funny thing is every ones got something to say about the d max. my favorite one is only good diesil is a straight six or straight 8 cant make a relible v8. any one ever heard that one.:badidea:

Actually, what you need to tell your friend is "Thank you for your advice, I'll keep that in mind when choosing a truck". Not that you would listen to him or anything, but at least he will be off your back about it!!!! If you listened to the bad on all the trucks from all thier owners, you might as well come get one of my horses to ride around on cause all the trucks got a problem or two. I only have experience with 2 diesel trucks (now tractors are a different story), 12V Cummins and GM 6.5 turbo. The Dodge has about 600,000 miles on it and I love the "big rig" sound it makes with no cat or muf + tons of power after spoolup (it has a modified pump and wastegate), but did that guy talk about the reliability of the 24V injection pumps? My boss has 3 dodges with 24V jobbers and they are all on either thier 2nd or 3rd pump at 1800 bucks a pop. My personal truck (6.5 turbo) on the other hand is a dream to drive. Nice and quiet, smoother riding, and although it won't pull with the cummins or dmax, I can take a roughly 6000lb load and set the cruise on 70 and never look back. Stays in OD uphill and down and its all stock and get over 10mpg. So don't even listen to a guy when he starts ratting about how bad something is and praise his own stuff. HE IS the BS!

another thing you might want to tell your buddy is to go over to DTR's web site and do a search on the infamous #53 block on the CTD,he will learn a new definition of "cracked block",all trucks have issues,and we a get a ride on the pain train, sooner or later.:(

Little known secret! Cast Iron cracks too.

Modern metallurgy and computer aided stress analysis has dramatically improved the durability of all castings, especially Aluminum and Magnesium.

Iron heads are going the way of the hand cranked engine. When cars first came out, and Cadillac introduced the first electric starting engine, people said it would be too unreliable.

What I have read and heard... but never seen... on a F*** modular V8 or V10 is the right rear(#4,V8 #5,V10) spark plug may blow out due to thin area where plug goes in, is it for sure??? Don't know but if so then I'll have one in the shop someday.
Regarding the Dmax, only head related thing I've heard about was 1 with a right side gasket blown, again I heard it but never saw it.

About the Vega's... my dad told me horror stories about them, he was a dealer tech in Ocala when they came out, he SAW the problems they had.

Tell your buddy that cast iron heads crack under high heat and/or severe stress. This is what used to happen to the Top Fuelers when they ran iron heads and prompted the switch to Aluminum.


You won't find an iron head on any modern day race car or street car for that matter.
Only on old farm equipment. :D

Iron heads are old school and as Mcrat said will be obsolete even on Big Rigs in a few years.


Now if the Cummins/Ford guys really wants to dis the Duramax, they should be talking injectors......................................:ee k:

What I have read and heard... but never seen... on a F*** modular V8 or V10 is the right rear(#4,V8 #5,V10) spark plug may blow out due to thin area where plug goes in, is it for sure??? Don't know but if so then I'll have one in the shop someday.
Regarding the Dmax, only head related thing I've heard about was 1 with a right side gasket blown, again I heard it but never saw it.

About the Vega's... my dad told me horror stories about them, he was a dealer tech in Ocala when they came out, he SAW the problems they had.

The F150 5.4 certainly had problems ejecting spark plugs. They ended up changing the head design in that area.

The F150 5.4 certainly had problems ejecting spark plugs. They ended up changing the head design in that area.

Usually happens because the factory recommends the first plug change at something like 75,000 miles. By then the plugs have welded themselves into place. The tech removes the plugs damaging the threads in the process and then threads in the new ones, more than likely without Anti seize. A few heat cycles later........ poof!

One of my employees had a 5.4 F150 (2001?) and at 5k miles he was driving and heard what he described as a gunshot, then a loss of power and increased engine noise. It blew a spark plug out and Ford replaced the cyl head. Lightning guys have seen quite a few failures, especially when running a pulley.