fredw

here is a little info on the third gen
the Duramax 6600's horsepower and torque increase and emissions reduction are enabled by a strengthened iron cylinder block and a lower compression ratio. The lower compression reduces stress on the engine by reducing the peak cylinder firing pressure. This, in turn, allows more fuel to be burned - more fuel means more power - while the lower compression helps reduce NOx emissions. Lower compression also helps reduce noise and vibration, making the all variants of the 6600 a quieter and smoother engine.
A revised variable-geometry turbocharger also enhances the driving experience of the Duramax 6600. Aerodynamic changes to the turbo's vanes help tailor controlled application of turbo power for seamless and immediate response at full throttle. The turbo, which spins at up to 120,000 rpm, is high-speed-balanced, reducing vibration and resonance - and contributing to the engine's overall smoothness and refinement. The revised turbo also helps reduce emissions, while maximum boost remains at 20 psi.
Another new feature of the Duramax 6600's turbo system is the capability of the variable-geometry turbocharger to provide exhaust braking. This function is available on some medium-duty truck models and can replace add-on exhaust brake hardware. With the new system, braking is controlled by a signal from the engine controller and can be activated by the driver.
The comprehensive list of changes and upgrades to the 2006 Duramax 6600 includes:
Cylinder block casting and machining changes strengthen the bottom of the cylinder bores to support increased horsepower and torque.
Upgraded main bearing material increases durability.
Revised piston design helps lower compression ratio to 16.8:1 from 17.5:1.
Piston pin bore diameter increased for increased strength.
Connecting rod " I " section is thicker for increased strength.
Cylinder heads revised to accommodate lower compression and reduced cylinder firing pressure.
Maximum injection pressure increased from 23,000 psi to more than 26,000 psi.
Fuel delivered via higher-pressure pump, fuel rails, distribution lines and all-new, seven-hole fuel injectors.
Fuel injectors spray directly onto glow plugs, providing faster, better-quality starts and more complete cold-start combustion for reduced emissions.
Improved glow plugs heat up faster through an independent controller.
Revised variable-geometry turbocharger is aerodynamically more efficient to help deliver smooth and immediate response and lower emissions.
Air induction system re-tuned to enhance quietness.
EGR has larger cooler to bring more exhaust into the system.
First application of new, 32-bit E35 controller, which adjusts and compensates for the fuel flow to bolster efficiency and reduce emissions.
The Duramax 6600 also has a new intake air heater to reduce smoke and emissions during cold or light-load driving. The system features a 1000-watt grid heater located in the air intake duct, which is triggered automatically by the engine controller. It heats up the incoming air to speed warm-up of the engine.
In addition to 50 more horsepower and 45 more lb-ft of torque in the Silverado and Sierra, changes to the 2006 Duramax 6600 build on a host of improvements introduced for '05 - improvements that bolstered an already strong foundation. The Duramax 6600 features a rigid cast iron cylinder block with induction-hardened cylinder bores; four-bolt, cross-drilled main bearing caps; forged steel, nitride-hardened crankshaft; aluminum pistons with jet-spray oil cooling; aluminum cylinder heads with four valves per cylinder; integrated oil cooler and a charge-cooled turbocharging system. Features, such as easy-access fuel filter and timing gears, reduce maintenance time and effort.
A new, 32-bit E35 engine controller monitors and adjusts the engine's operation. Designed exclusively for the Duramax diesel engine, the controller helps the injectors precisely meter fuel to the cylinders and can compensate for the variability of the injectors and fuel flow. This sophisticated, more powerful controller also can support up to five injections per cylinder and eliminates the need for an engine-mounted drive unit to fire the fuel injectors.

Lrdchaos

Good for you........My dad has over 150k on his 02 dmax and hasn't had any problems so I guess that makes it a perfect motor....by your reasoning. Not saying that I don't like the cummins just saying the the dmax is a good motor also. All I am saying is that all motors and truck man. have their troubles.....even Cummins....................Time to accept the facts.

whtractor

i had a 99 24v, 3/4 ton, 5 speed, 4x4, onelift pump and a injector pump got a 196,000 miles befor i traded it in on my new one. They gave me $8500.00 witch payed it off, sweet. Loved that truck, Brother-in-law would drive it a cry because it seamed to pull better and run faster then his 2003 Ford PSD, How much HP and Torqe to ya really need, How cares if another brand as a biger an faster engine. Lets see 5.9 v what a 6.6 or whatever it is, How about cummins builds a 6.6 and lets see what happens.

Why do thay make tractors so big, with so little HP, My tractor is about 8500 lbs and only a 102 Hp, but the thing makes my truck look like a Match Box car, I love driving that thing on the road you could not imagine the looks i get in Houston. whooo. Look at that RED NECk kids.

Bart Timothy

FWIW, I asked Brett Suthervatter, one of the original founders and owners of Edge products, about the "bombability" of the new '06 Dmax. He claims there is less head room for increased performance with the new engine in the after market business. Raising the stock power level hasen't increased the overall potential of the engine. GM is just squeezing a litttle more out of what was already there. But his opinion is, the Dmax is a pretty tough engine, never the less.

nickleinonen

isn't that the same with pretty much all slushbox transmissions??? [the only time i have never seen one downshift is when the vehicle speed was at a point where the downshift would result in engine overspeed]

countrycoach

For staters thanks for clearing up the tq curve thing for me. I have never looked at a tq to know that. Second I have a 6.5td that everyone knows to be a crapy diesel. It is a 94 with 200,000 miles and has pulled a hourse trailer pretty much all its life. I have put one lift pump = 80.00 1 pmd=400.00 and one rebuilt injection pump =800.00. So from what yall are describing my truck is just as good as yalls! Face it dodge boys, you finally have some competition in the diesel market! This year is going to be a big mile stone for the dmax engine in the aftermarket world and racing! You are going to see some records broke and alot of dmax's up front in the sled pulls. The independent front end is working out nice for setting up for a pull and with the rpms you can turn in a dmax you can really get the sled moving! There is no better diesel right now. Yall keep braging about the reliability of the cummins but the new version has only been out for a couple of years now. It seems to me that yall are comparing apples to oranges. You are comparing an old 12v or even an old 24V to brand new engines that have alot stricter emissions requirements! Lets give the newest cummins a few years and see how it holds out before bashing chevy!

omaharam

You guys all have little decals on the back window of calvin peein' on a chevy emblem don't you?

Take it easy. There's no need to get all riled up. Everyone will form a personal opinion on the new Dmax. Guess what? It, in no way, shape, or form changes the truck. Some will like it and some won't.

By the way, vanilla is better than chocolate and blondes are better than red heads.

MikeyB

After reading fredw post on the changes to the new Dmax I'm really wondering what the fuel economy is going to be. Lowering the compression, reducing peak chamber pressure and increasing the fuel rail pressure may decrease the fuel economy. My thinking is GM is going for major HP gains with a big hit to fuel economy.

MikeyB

MCummings

Not Really. Real auto transmissions don't.

Merrick

hovisimo

i don't know why we as humans need to continuously compete with one another and rank things. there is no absolute objective best. i feel we have the most heavy duty of the big 3 diesels with the longest track record, but negative personal experiences always take precedence over that. hell i had my entire block replaced at 19,000 miles. but it still runs and gets me where i need to be, always has. why can't we just enjoy our trucks? i don't really see ford or GM as competetion for some reason.

Lil Dog

Two things..

I guess firstly, Cummins will have to finally go into the lower end "light Duty" versions of their engines to compete. That is where you find the balance between reliability and power. Light duty will bring down the standards, but that doesn't seem to affect the sales of Ford or GM.. I will stick with the Medium duty diesel thanks..

The torque talk.. Yes there was a fair description of torque and how it is measured. There is one problem with these big torque numbers on the V-8s and that is that they have a physical handicap. Torque is a function of stroke and rod length ratio and number of throws on the crank shaft. So you can throw all the fuel you want at the small bore short stroked V-8 and get about the same torque now with electronics. The electronic injection pulse control has given this handicap less of a value and makes them a "contender" in the torque field. However the effieciency of the the machine is sacrificed to achieve the same values. The I-6 can achieve torque down lower, probably at a better fuel rate because of the geometry advantage and then maintain it over a longer RPM band.

If you are a drag racer, the long stroke and rod length then becomes a problem in achieving Peak HP Rpm in a short time.. Something the DM has proven to be good at due to the shorter throw etc.

The 6 and 8V92's were good with Auto's too, but not much for a highway tractor.. Good race engine though..

ridofpwrstroke

Just be happy we all dont have the 6.0 from ford. Reading their forums makes me feel good about my truck. A buddy was looking at getting a diesel this year. I told him to look at the GM and the dodge. After all was said and done, he bought a dodge. I am not biased. I still think I am a ford guy. I own two ford products as we speak. Not diesels though. I buy what is the best for me. I own an arctic cat, and two ski doos for snowmobiles, a polaris and a kawasaki four wheeler, a new volkswagon, 1 dodge, and 2 fords. I buy what is the best at the time of my purchase. I like the DMX. I think it has come a long way and I dont hear of to many problems. In 02, I got rid of my 7.3 powerstroke because of many problems, hence the screen name. Most 7.3's are great, I just got a bad one. I like the DMX because of the auto (but dont care because I prefer manual and bought a manual cause I like rowing through the gears and for towing), real crew cab, smooth ride, and they look sharp. At least the GMC's do, not crazy on the chev's. I like the dodge because they have been using the same motor for 17 years or so. Sure, there have been refinements, but pretty much same motors. Fuel economy on my buddies trucks were alot better than my ford. Most big rigs and heavy equipment use I6's so they must know something that others dont. They may not rev as high as the other V8's, but I didnt buy my truck for that, I usually use it to tow. I like running big tires. I like trucks that sit high. I put on 35's with just a leveling kit. The chev's need a very expensive 6 inch lift to run them. The simplicity of a solid axle is a great concept. I put lockers in my truck because in the winter when I pull the groomer around to different trailheads, I got pssed off because I was sick of the "one wheel spinning on both axles even with a rear limited slip" so I easily upgraded to selectable lockers. U-joints in my opinion are easier to replace and much cheaper. The drivetrain on the dodges was much beefier. The engine compartment is less cramped. When I put my 4" exhaust on my 7.3, I had to bend the firewall to fit it in. Plus everything was so cramped. The six cylinder has so much room to do maintenance. Plus for modding, nothing can respond to so much with so little money. Very easy to mod. I also like the way the dodge looks. Looks like a "mans" truck. Does it ride as nice as the DMX? NO. I overlooked that. Plus the cummins sounds like a real semi driving down the road. I have replaced the VP44 once and the lift pump twice. I also demand alot of fuel. If I were to buy a new truck right now, I would look at the DMX, but I feel that dodge still has a better motor in their truck. If they put a cummins in a ford, I GUARANTEE I would get the ford. All 3 different websites admit to the cummins being the best diesel motor out there, it is the other crap that goes wrong with the dodge. I overlooked that. I am still glad I bought the dodge. Now if dodge would make a cummins with the same quietness as the new trucks with the mechanical fuel pump, NO ONE could touch these motors. They all have their problems, but I have had less problems with this truck. My 98 that I just sold that my wife was driving, had 130k on the ticker with absolutely no problems. None. I wish I could say that about my 24V. I think if GMC had a solid axle, it would be a hard truck to overlook. Both the GMC and Dodge are solid trucks, just be happy you didnt buy the 6.0. That site is awesome to read. Peoples comments are: 2 trucks bought back from ford, I hope this one is better, but I would rather be pushing a ford than driving a GM or dodge. Well, most people are pushing them. So you cant blame them for that.

countrycoach

Well Said!

Lrdchaos

Nice post....

CTD NUT

Yes, you are wrong.....the original Dodge CTD in 1st gens had many differences compared to the 12v 2nd gens. Like the 1st gen VE rotary/vane pump, non-intercooled, different turbo, etc. 94 was the first year for the HX35 12cm turbo and the P7100 pump. It seems DC and Cummins can only hold onto an engine/parts combo for about 4 years or so before major component changes take place.