Duramax is getting better

[Ncostello]

Seems as though GM has made several noteworthy improvements in the 04 Duramax. Many things like injectors, fuel filtering, external injection lines, very easy to change injectors, variable vane geometry turbo, improved EGR system and many other things (I cant remember them all). This engine code LLY should be a major improvement in the Duramax lineup.



Its good to see them fixing the problems that owners have had to deal with for the last few years. One thing I read was that all trucks get a high idle button standard. You could add one by connecting to a ECM pin before... but now its stock.



Cummins... make DC wake up and give us a high idle manual toggle switch!

 

[Torque King Jay]

Ncostello they have made some pretty good improvements to the motor. I was at the Duramax plant about a month ago and they were in full production with the new improvements. They started implementing them late in the year last year. I don't know if they can do much more on this platform of block and head that they are currently running right now.

 

[Ncostello]

I read where the injectors are very simple to change and take only a short amount of time. Also read where replacements are around $60 each which is much better than having to pay several grand. My information is from GM-Diesel.com threads covering the LLY engines.



I like to follow all three diesels and see how each solves their own problems. GM at least seems to be making real improvements/major changes to the metal parts... and not just reflashing computers or turning off features like Ford. I know Ford couldn't just redesign the 6. 0 in its first 6 months... but it will be interesting to see how they handle it in the next year or so.

 

[Gary - K7GLD]

Comptition is GOOD - so are forums like these, where problems are brought out in the open for discussion - it a cinch the guys over in the GM forums who constantly banned complainers or shouted them down did NOT contribute to fixes for their problems!

 

[Ncostello]

Competition is almost necessary. Otherwise future Dodge innovations and performance parts come at a slower pace. I'd be watching future Duramax pullers. I'm not saying they are king but from what I saw they offered the best competition to the Dodge. Fairly stock looking Chevy/GMC's were out pulling some supposedly Bombed Fords. At least thats been my take. I hope they do sort the bugs out this go round.

 

[Breck]

I don't think the engine will be much of a problem it is the rest of the so called "HD" that is lacking.



Beef up the front end, put a real box that doesn't fold under the pressure of your palms pressing on it, get the thing off the ground and put some real tires on it and maybe it would be more worthy at looking at.



Until then... it is just a "suburbanite" truck, that was built for 36-48 month ownership/lease.



Isn't GM a bank and leasing company that happens to build autos now?

 

[Ncostello]

Actually GM is a pension fund (sort of). They build and sell cars to pay for the pensions of retired employees. They are now at a point where they have to sell cars to pay that... and not much of anything else.



Not a thing against those retired from GM. It was promised to them and should be paid. I hope I'll someday have pension or SS. But companies like Toyota have average age employees much younger and their money earned from sales goes toward other things. Its just the cycle of business for US car companies they are now in. It doesn't do well with competition.



Guess I'm getting way off topic.

 

[Ncostello]

The other two fire departments in our township got new trailer towing rigs today. One was a F450 6. 0 and the other was a Duramax 3500.



The Duramax truck has the improved LLY code engine which has all the major improvements. I must say it sounded good and looked fairly simple under the hood as compared to the PSD. To me it is the new competition. The Chief of the department who got the Duramax drove both... and his opinion is the Chevy felt way more powerful by seat-o-the-pants meter. Acceleration felt much better he stated. And he could care less one way or the other... just stating it the way he see's it.



I could tell it was the improved model with the external fuel lines and the VGT turbo with all its sensors. We need to keep our eyes on the new Duramax Diesel I think.



I think 310HP and 590 TQ were the numbers associated with the Allison it has.

 

[QRTRHRS]

While waiting my turn at a toll booth this week, I saw a GM 5500 four door with the Dmax pulling a Home Depot sponsered race trailer or something. One of those that looks like it has a cab borrowed from the full sized van. The rig was orange and black with lots of chrome and looked sharp. Only two wheel drive I suppose but my point is, the 5500 rating. Are you listening DC?

 

[DPelletier]

With all do respect, I'm not sure we "need to keep our eyes on the Duramax". I'm not the least bit impressed. 310/590 compared to 325/600 AND only available with the power robbing Allison which defuels in first and fifth. So I guess even the rated power is misleading. Don't forget the VGT and EGR system. I have to agree with Breck. The GM is a civilized, car-like truck that is good 'til the lease is up. On the other hand, with ford's 6. 0 PSD disaster, the DM is arguably the closest competition to the Cummins Ram. It's just not that close.





Dave

 

[datablitz]

QRTRHRS, just move to mexico, they have 4500,5500, and i think 6500 down there.

 

[Ncostello]

I saw a fairly harmless looking Duramax do fairly well at Scheids pull this past summer. It made some fairly bombed Powerstrokes look poor pulling the sled. The Duramax quickly spun up to a medium toned power level and remained constant sounding... and kept pulling along. I thought he was gonna go full pull... but then the sled brought it to an instant stop near the end.



The Powerstrokes ramped up then the rpm's kept dropping off until they came to a slow stop. They sounded like they were struggling the whole way whereas the Duramax's at least sounded good until the end. I know this doesn't prove anything except my gut feeling that I'd rather have a max than a stroke.



There will probably be an electronic widget that will prevent the defueling. I'd still rather have an Allison than a DC transmission. And I have 250 HP (estimate with RV275's) so 310, 320 or 325 HP is more than I'd want to tangle with.



I know the Dodge has more power... I'm just trying to make some light of what else is out there to contend with. The ole classic GM/Ford/Dodge battle I suppose.

 

[DKarvwnaris]

I was really hoping the duramax was going to be a contender and a reliable powerplant as my wife wants another suburban to pull our livestock trailer with and to keep me from repowering our current one with a cummins.

Hopefully the modifications will prove to take care of the majority of the problems most of my fellow friends have been having with theirs. Most have traded theirs in on cummins powered trucks again.

I am not so sure the head issues will be solved with this, but there is hopes it will be a revision they don't mention so as not to admit fault, yet still fix the issue.



That Jeep 5. 9 is definitely catching my eye DM is showing off at the shows, but I have more faith of GM improving their engine than DM actually producing such an overpowered sport utility.

 

[Ncostello]

From the 04 LLY code article over on the dieselpage.com... the heads were part of the improvements... most notably the external fuel lines to prevent fuel leakage and make injector changes simple. The valve covers are totally different to to accommodate the changes. At this point I'd feel they were as reliable as ISBe's but only time will tell. Its hard to beat Cummins Engine in the reliability catergory.

 

[DPelletier]

Neil,

I agree, I'd rather have an Allison 1000 than a 48RE too. One more gear, if nothing else. As far as the defueling goes, they may get a "widget" to deal with it, but its still false advertising as far as I'm concerned. Besides, we're comparing stock to stock.

GM can aspire to getting the DM to be as reliable as a Cummins, but they have no hope of getting the longevity to the level we enjoy. None.



Dave

 

[Big_Daddy_T]

Someone posted failure rates on another site and the allison was dead last. Its just a name.

 

[Kyle03D]

Please elaborate on the head issues. I am interested as I have yet to hear of a failure.



Thanks

Kyle

 

[Ncostello]

I'm not exactly sure but on the previous heads the supply lines (I believe) were internal. From what I gathered... some leaked and I think I read where some rusted internally (I dont know how). These leaks would flood the crankcase. Also the injectors had some issues and were a challenge to change. Not exactly an afternoon job in the drive for a so-so mechanic. Thats all I know and its just from reading elsewhere. I am not too familiar with the Duramax.



Talk with Rebel Horseman... he had these problems and switched to the Dodge Cummins. He's been there before.