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J54 Mark
02-23-2004, 13:39
The owner of the largest diesel shop in the area just told me not to buy a Duramax because of the aluminum heads. With absolute assurance they stated that the heads will warp.

Now, we need only to read these forums to see that the Duramax trucks are not problem free, but I have never heard or seen an actual case of head failure on a Duramax of any kind - and I've talked to a lot of owners.

With the duramax entering into its fifth year of production, this canard about aluminum heads is getting tiresome. So, my question is: Does anyone know of a documented case of head failure on a Duramax, anywhere at any time?

Mark

[ 02-23-2004, 01:07 PM: Message edited by: J54 Mark ]

deerhunter7
02-23-2004, 14:35
All I've heard of is a couple of head gaskets , no warped heads.Did you ask the place if they had any or was he just blowing smoke.. Some rumors never die..

drgracr
02-23-2004, 18:32
just my 2 cents, I agree with deerhunter7. besides there are just 2 many headbolts on this engine for a head to warp....imo

dmaxmule
02-23-2004, 19:12
For what it is worth, My friend works at a vehicle test track in Ohio. I always talk to him about new vehicles and how they are doing. When I deciced to buy a diesel, I asked about the dmax. He said he did not know very much that everyone of the motors ended up with head problems. I think he said cracked heads. He said no truck ever made it far enough to test anything else.

The conditions under wich they test these truck are unreal. They put several tons of weight in the bed. It is so much that they had to build a weight to hang on the front of the truck which weighed about one ton. They also put a thing(like on a semi to get wind over the trailer) that is so tall he could not reach the top of it when he was standing in the bed. He is alittle over 6 feet tall. They the do test around there tracks:high speed, cobble stone and things like that. They push the trucks to the limit.

This was before the LLY, but he told me about it and said for me to wait on it. He did not say anything about how it tested.

He says cummings makes the best motor, but it is put in the least of the three major trucks. He says Ford makes the best truck and GM makes the best ride. He says to pick the best suited for what you are doing.

On the other hand, I have never heard of head problems out in the real world, so I am buying a dmax. Thanks dmaxmule

Chris N5CWM
02-23-2004, 19:39
Cummings? They make motors? Electric?

CUMMINS (no G, next time you see one read the label!) builds engines not motors.

Sorry I couldn't help it!

tongue.gif

Aluminum heads will warp if they are overheated.
The aluminum head and iron block expand and contract at different rates and if there is excessive heat and/or pressure the head gasket will fail. Enogh heat and there will be warpage.
Of course under normal operating conditions, the DMax's aluminum heads will not warp. We all know that!

Some rumors (heads warping) never go away!

Jomar
02-23-2004, 21:06
In my 50 years of fooling around with engines I`ve seen gobs of cast iron heads that were warped or cracked but I have not heard of a single Duramax head warping. Not saying they won`t under certain conditions but like the old saying goes, " I`ve seen people that could tear up a crow bar too. " IMHO you made a good choice in the Dmax, dmaxmule.

Jomar

310-MAN
02-24-2004, 07:01
Hi..Last year I had a head gasket leak on my 2001 D/Max. When the dealer removed the heads to replace both gaskets as a precaution. One of the heads was "etched" where the gasket was leaking, so they replaced that head with a new one. This is the only instance I know of where a head has been replaced. 10,000 miles later the truck is still running great. JG

D-max Man
02-24-2004, 08:38
Originally posted by dmaxmule:

The conditions under wich they test these truck are unreal. They put several tons of weight in the bed. It is so much that they had to build a weight to hang on the front of the truck which weighed about one ton. They also put a thing(like on a semi to get wind over the trailer) that is so tall he could not reach the top of it when he was standing in the bed. He is alittle over 6 feet tall. They the do test around there tracks:high speed, cobble stone and things like that. They push the trucks to the limit.
I am spent 4 1/2 years at the GM Proving Ground in Milford, MI. (I am not aware of a GM test facility in Ohio but it could be a contract testing facility I suppose) and my job duties included "Abuse testing".
I am familiar with the trailer simulators you speak of where they use trailers with a large piece of lexan attached to the front to simulate a large box trailer and they ballast the trailer to the desired weight.

We usually tested the trucks from max GVW-GCVW to 25% above max GVW-GCVW. I am not aware of any fixture for putting 2000 pounds on the front of a truck however. We did sometimes add a few hundred pounds to the front to simulate a cab over camper or the like but 2000 pounds hanging off the front seems a bit excessive.

Several tons in the back and 2000 pounds on the front - Under those conditions, any "pickup" would fold in half.

I have also been involved in the warranty aspects of the Duramax while I worked for Isuzu and I still have many connections there. I am aware of a few head gasket issues and leaking injector sleeves but I have not heard of any warping issued at all.

These engines passed severe thermo shock testing where all the coolant is drained from the engines and they are run on the dyno until they are very hot, then it is flushed with cold water. They passed this test with flying colors.

I would ask your friend to produce proof of this (he may not be able to though if he is involved in testing) before I would take it as truth. I had someone tell me once that he knew of a dealership that had 6 Duramax

Kennedy
02-24-2004, 10:33
CJ,

Been trying to reach you...

dmaxmule
02-24-2004, 17:33
D-max Man
I just read my post for the first time. I had no time to proof read it yesterday. It was a one half ton weight, not a one ton weight. Sorry for the confusion. It is a not a GM facility, they test all types of vehicles(BMW to Dump trucks). The trucks had a wing like thing that caused wind drag. I do know any more details except for how tall it was.

I highly doubt he is telling a lie since he has been around my family for twice as long as I am old. I would trust him with my life, so I do believe him.

He said they put the dodge thru the same test several years ago. The motor done great, but the truck did not do so well.

P.S. He does not drive any more because of a bad back and cannot take the abuse, but he works in the garage now. thanks dmaxmule

TanM998
02-25-2004, 04:59
The only issues that I have heard from the warranty side of things is that the Dmax can start to burn down pistons once they have been modified. I know several Dmaxes that have been in for engine replaces due to pistons burning down caused by increased power from a computer chip or other means of performance enhancers...

Scott
'85 Tan M998

mark45678
02-25-2004, 16:56
burnt pistons???? I see ALOT of guys running EGT (1500~1600 *F)that would melt any alloy and NO ONE has SAID A word about melt downs!!!!! M tomac,JK, and MANY others running WELL over 450 REAR wheel HP haven burnt down ! so I challenge you to bring some one to the forum and enlighten ME! the duramax is a ROCK solid motor and thats that!!!!! I smell bad press!!!! :rolleyes:

SoCalDMAX
02-26-2004, 13:03
I think someone is a little confused as to cause and effect.

I had an injector stick open, which is either a defect in the injector or enough dirt passed through the substandard factory fuel filter to make the injector stick open.

Since the injector was now injecting fuel continuously rather than the very short bursts that it should, it actually burned through the piston. The head was removed and the 3 remaining pistons on that bank looked like new.

If increased timing and pulse width could cause such high temps in the cylinder, all 8 pistons should be equally or nearly equally damaged. I'd love to see pics of that myself, since I think the Duramax is nowhere near it's power handling limits in regard to the bottom end. For me, the relationship between cause and effect is based on actual observation. If all cylinders fail, something affected them all equally. If one cylinder failed, then a component affecting only that one cylinder is at fault.

If you recall, the Pike's Peak racer was built by GM and produced over 600hp, mostly through tuning (and possibly a different turbo?). My *gut feeling* is that another 300hp more could be made without having to modify the internals of the engine. Of course I don't think one should expect warranty coverage or 500,000mi of reliable service either, at that level. ;)

mark45678
02-26-2004, 18:47
SocalDMax I agree 100% with your statement of a stuck injector but a blanket statement like engine modes burning it down...... I dont see it!!!! :rolleyes: I get tired of defending our dmax to those how want to give it "bad press" the few how post bad heads,bad turbos,bad injectores......I dont have rose colored glasses ,I have seen a 2002 with bad head gaskets and 4 injectors 4days later...I know these things go wrong... Sorry if Ihave flamed any one here ! smile.gif

hd90rider
02-26-2004, 19:26
I had a head crack around 100k Took the dealer a year to finally "hot test" it . I kept losing coolant for a year,and every time I took it in they found a leak somewhere else. Finally they put pressure on it over nite,and could see no leaks but coolant was down. Called GM & they told dealer to check left head.( Now how did they know which one was bad??!!!!!)Anyway the crack was hairline & only showed up with the "hot test". They must have had several others for them to know which head to test!!!