Heavy Duty Truck Diesel Engine Wars continued

Diesel Engine Wars continued...

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June 2008 - Now the World Knows -

CAT bows out. Cat's claim is they played a strategic maneuver because their world changed when the Germans bought Detroit Diesel. I say that may be true... as it would seem they(Cat) were real stupid in stumbling with the Oct 2002 emissions standards, then making a late introduction in 2004 a complicated, expensive, high part count ACERT twin turbo technology. Hindsight makes ACERT look like a patch that would work on all of Cats existing engines, carrying them through to the point where they would publicly focus on a new engine strategy...

Cat brazenly told the world ACERT was the technology of the future, but many onlookers scratched their heads. Cat, along with the rest of the industry watched Cummins nearly loose the farm(very high warranty costs - lost market share) a few years before by ignoring the KISS rule by intorducing a complicated cross flow liquid radiator cooling system to cool engine intake air as opposed to the much simpler charge air (air radiator) cooling every one else settled on and that Cummins ultimately ended up with, too!...

We see now that Cat is not stupid. Cat probably saw the squeeze coming a long time ago... Penski's Detroit Diesel Corp introduced their series 50/60 big block diesel engine during the 1989 time frame. industry watchers were suspicious, as the Freightliner-Penski relationship blossomed along with Penski's Detroit Diesels new Series 60's sales. Later, when Dalimer bought a minority stake in DD from Penski, (I think 20%) and Volvo parted company with Cat - Cat probably saw that to compete, each of the worlds major truck manufactures would have its' own engine... the result: Cummins and Cat would be fighting for a number 2 spot? Not so good.

Well, maybe not with Navistar, as at least short - mid term, they(Nav) lack ownership of a big block? Maybe Navistar might be someone to talk to?

A partnering of Cats hydraulics, engine and automatic transmission with Navistar on a world construction truck... market to the world. There is a lot of money and thought behind this strategic retreat. Meanwhile, Cat says not to worry, they claim they will be around to service the million plus engines they have out there. I hate to see them go. td

Jan 2008 - there is not anyone who will print what they really think about the new engines - too much money involved - someone could get sued if they are not very careful - I too, can't and dont print all my secrets. My customers run both Cat and Cummins - there have been recent times where I have recomended one or the other for very different reasons. Yes, I have post emmision Cat and Cummins running successfully. Which is best?

Cats rings and liners will probably last longer because Cats' ACERT "dual turbo" technology cleans the exhaust before recirculating it... CAt offers long, $0 deductable warranties. (to at least 84 months and 700,000 miles)

Cummins sliding port opening in their turbo is an elegant, simple design to port recirculating exhaust gasses back into the intake side. Introduced in 2002, the Cummins EGR design has evolved into a reliable engine technology. Cummins extended warranty choices are very limited - by comparative standards (cummins strongest, currently published, warranty cuts out at 3 years and 400,000 miles).

On one side you have simplicity but a shorter life expectancy - on the other, layers of complexity, available long warranty backed by a huge company and potential very long life.

Fuel mileage and performance issues between the two engines are much more nuanced, making exceptionally strong blanket statements in favor or against either, in my experience, suspect.

On 07 engines, sensors, not necessarily the sensors supplied by the engine companies... cause as many, if not more problems than anything else. These are simple bug issues that will get worked out as road miles go up and the bugs continue to be exposed. Remember, nobody, certainly not any of the major manufactures want a black eye after the recent new product introductions. Communications is a concern.

Choosing between

C15, ISX...

Is it both?

The Cat ACERT has more parts and complicated procedures than the ISX, is about 300 hundred pounds heavier, should last a million miles, has great purchasable warranty available.

The ISX is fuel efficient and responsive, usually costs a little less than yellow iron and features simple processes relative to the C15 ACERT.

But, the ISX has a dirtier Exhaust Gas Re-circulation process... which, in theory, will shorten the life of the cylinder walls and piston rings along with potential extra soot buildup on the valves... to something less than a million miles?

It is a judgment call

Feb 2007

The end of the month and into next month we will see first production releases of the particulate trap engine. Cummins and Cat both need to occasionally achieve very high temps in the exhaust system to burn the soot they capture into ash. All truck manufacturers need to make allowance for the extra heat produced.

Also, just now an unanticipated effect of the combination of Ultra Low Sulfur fuel, soy diesel and zero temperatures is an additional complication for cold country truckers. 1/2007

Feb 2006

I don't think anyone who is dragging 80,000 pounds (or close) is getting fuel mileage to brag about unless they are using a bag of driving tricks that very few take the time and effort to practice or even learn. But, dropping down to 65,000 pounds or so, there are any number of success stories out there. The sixes, into the mid eight mile per gallon range is common enough for those with aerodynamic trucks and who practice the basics of fuel efficiency procedures.

All that is due for more change a few months from now as the even newer technologies involving no sulpher engines & exhaust particulate traps. Not many people think much of the engines with the 2002 round of changes (the EGR's and the ACERTS) and for good reason they will think even less of the January 07 engines! Costs, weights, complexity and worse fuel mileage yet are the concern of all involved.

June 2005

On big block engines it looks like it is turning out to be a draw between two of the biggies... while Cummins and Cat have gone their separate ways: Industry accepted EGR technology for Cummins and Cat with their own ACERT, neither can claim absolute victory and both have particulate traps in their futures(2007).

Cats' C15 ACERT looks like it get its' best fuel mileage at close to 1300 RPM and depending on the weight hauled, has the torque at around 1100, that's deep enough below the fuel RPM target to hold gears and provide acceptable drivability. Cat would have its' customers make up for the loss of engine speed by gearing slightly faster... typically as slow as 3.36 or faster yet with 3.25's or even 3.07-8's vs. the former 3.55's... and making an attempt to convince drivers to drive a bit slower too...

The Cummins ISX which seems to get its best fuel mileage at close to 1400RPM, is about 200 pounds lighter than the C15 and three thousand or so fewer dollars. At 1400 RPM peak fuel the ISX gets by with the pre 10-02 gearing thus holding on to the drivability that the slower gearing offers.

Still, in general, Cummins or Cat speeds need to drop 5 MPH or so from former speeds to stay within range of the pre 10-02 engine.

Cummins is charging from a 20 or so year position well behind Cat in terms of acceptance by owner operators as the engine of choice for their truck. Now, on paper, it looks like the drivability edge for a given horse power and torque could go to Cummins (few power complaints) and certainly, at this is written, Cummins has a several thousand dollar price advantage in a competitive market place. Could be interesting ! :) as this could turn into a real horse race, as this time, Cummins is right in there!

NOTE: If you are buying one of these new engines, buy the premium reporting devices that is available for them... Road Relay by Cummins or Cat's Messenger... these engines are both fresh enough to need a active monitor... this will help the driver improve fuel mileage as it reports point and average MPG, this is an invaluable tool that will give a payback relative to the importance you place on fuel consumed.

ISX (basic platform introduced in 97 as the Signature 600) NOTE: Engine Platforms tend to develop over a long period of time. Conceptually those blocks designed longer ago would have the most difficulty adapting to the rapidly moving EPA targets. The basic 855ci block of the recently retired N14 was based on was first introduced nearly 50 years ago. It required too many changes to meet emissions and had to be dropped.

Cats' C15's forbearers were several generations of the venerable 3406 dating back to the early 80's.

I don't hear much of Detroit since they stopped being sold to the wider trucking world. I have been told the Germans are pushing some Mercedes Benz engines that are getting some pretty good fuel mileage and offering 750,000 mile warranties.

I have also heard that the Volvo engine is not all that bad. The problem, always has been with a foreign to the USA built engine inside the USA is parts and the ability to service the engine... most often leading to down times longer than with domestic engines. Most often, this type of history repeats itself.

It will always be true that -when it comes to trucks, there is nothing more thoroughly unproductive than... down time.

December 2003

So far so good on the new engines. Of course we probably wont know much until a body of these new engines have a few hundred thousand miles on them.

We have a fleet of about 20 of Cat's new ACERT engines running and no complaints so far. We have a few ISX Cummins out there and no major issues. I can't say much about the Mack, Volvo or Detroit engines, either. I don't sell them. I have heard some rumors about each both good and bad.

It is hard to gear a truck using the Cat guidelines. 1325 RPM at 65 MPH. Most often this means 3.36 ratio. Fast! This means running in what I call "torque moan" territory. That is the low RPM noise you hear when every bearing and piece of metal in the drive train is sounding off because of all the torque it is being subjected to. So, I am playing it safe and gearing at the more traditional 3.55 ratio. May suffer a bit on fuel milage but save an expensive metal fatigue breakdown. Cat is advertising peak torque at 1200 RPM ...I believe running long, just 125 RPM away from all that peak torque power and harmonics is sure to be dangerous.

Spring 2003
Detroit Diesel, Volvo, Mack, Cummins... they have all added exhaust gas re-circulation (EGR) to their Class 8 Heavy Duty Truck engines to help meet the EPA 2.5 gram per horsepower hour requirement put into effect by the government in October of 2002. This process puts a large additional heat burden on these high horsepower, high torque engines. The process is common in passenger cars but largely untested in the heavy duty truck marketplace.

With truck components, it is well known that an increase in heat most often causes an increase in wear. Also, most often new technologies applied to a working heavy duty trucks take some years of refinement before they work reliably in most applications. Wise truck buyers are concerned.

Caterpillar elected to miss the governments October '02 deadline and chose a group of soon to be released technologies they call ACERT, to meet the 2.5 gram EPA requirement. ACERT will release about a year late. In the interterm, Cat dropped a few of their horse power settings and is now building and selling what they call a "bridge engine" about 3.3grams (C15 engine) and expecting to pay the EPA a fine for missing the Oct. '02 deadline.

Without question, the Cat bridge engine is the safer bet, just now. On the 3.3, Cat changed the engines timing a bit and added a catalytic converter to their existing, pre Oct 2002 Class 8 engines. This minor change chopped a few percent off their pre Oct. 2002 engines fuel economy (about the same as their competitors lost by going to EGR) but, importantly, they did not pump a bunch of heat back into the engine. So, essentially Cat is now selling a slightly modified version of a well proven engine and the competitors are selling an engine with significant change and as yet unproven reliability. This is a temporary, but significant, competitive advantage for Cat.

Meanwhile, Cat's ACERT engines are just around the corner and full of uncertainty, too. What early on was billed by Cat field representatives as a relatively simple extension of Cat's existing hydraulically activated unit injector technology they were using in their existing smaller 3126 class 6-7 truck engines, looks now, to be much more complicated.

The stakes in this battle are enormous. Cummins appears to be literally betting the company on their success in introducing EGR into their ISX and ISM engine families in class 8 heavy duty trucks. Cummins is a diesel engine company and basically only that, they don't build trucks or bulldozers. Cummins loss of market share and product issues in the Class 8 truck market place over the last decade or so, along with increased competition in other diesel engine market segments; have left the company vulnerable.

Cat is arguably playing with big fire in missing the Oct. '02 deadline. The size of the EPA fine Cat will pay is less than certain (no doubt their competitors are politicking in every way they can for a huge one ). Cat, a very big boy, with big boy competitors politicking against them, facing the US government down over a big national political issue. Fights don't get much more interesting than this!

Meanwhile, the marketplace is no more certain about the seemingly, now, very complicated Cat ACERT technology than it is about the EGR technology that all of Cat's competitors choose. Caterpillars' bet is certainly a billion dollars big or more with market share on the line and big fines, for sure.

This situation with Cat is a bit ironic because in the middle late 1980's Cummins bet on a technology called 'Low Flow Cooling' when all the other diesel engine manufactures went to 'Charge Air Cooling' as a treatment to cool compressed intake air from the turbocharger to the intake manifold for a cleaner burn. Many LFC owners were less than impressed with the product. Ultimately, Cummins gave it up and by '92 switched to 'Charge Air'.

Detroit, Mack and Volvo have less at risk. Since they are owned buy OEM manufactures, if their engine(s) do pan out poorly, these truck manufacturers can and I believe, will keep doing some business with Cat, Cummins or both, hedging their bets against their own engines.

The risk to the individual truck owner seems to be the greatest of all. Accustomed to engines sold with free warranties out to 500,000 miles and a typical engine life approaching 1,000,000 miles, truck buyers don't know what to think when the base engine warranty is a grudging 2 or 3 years and if available, an arm and leg in up front costs to extend beyond that. In some cases, even the purchased warranties don't cover as much as the old freebee of time past. In a very competitive, mature industry such as trucking; often there is not enough profit margin available to add such risks. Particularly troubling, is some engine manufactures apparent lack of faith in their own product by refusing, up front, to stand behind what they want to sell beyond what the unimpressed might view as the shake down period.

In this environment, it is easy to imagine a major engine failure, long, long before the truck is paid for. To their credit, Cat is the first to recognize the importance of this issue. Cat has released (May 15, 2003) a comprehensive group of optional warranties that extend out to as long as 84 months and 700,000 miles for most heavy duty engine components. In most of their engines a separate, 5 year 500,000 mile optional warranty is available for injectors. Unheard of!

The last shot has yet to be fired. The diesel engine wars will continue...