## Mercedes-Benz Will Offer Tier 2 Bin 5 BLUETEC Diesel SUVs in 2008

##### 25 September 2006

Mercedes-Benz today announced that it intends to offer BLUETEC diesel-powered versions of its M-, R- and GL-Class sport-utility vehicles that will meet EPA Tier 2 Bin 5 and CA LEV II emissions standards in the US beginning in CY 2008. (Earlier post.)

When the Mercedes E320 BLUETEC hits salesrooms shortly, it will be as a 45-state compliant vehicle, not a 50-state vehicle. (Earlier post.)

To tackle the difficult NOx target in the Bin 5/Lev II standard, DaimlerChrysler has defined two technology approaches.

The E320 BLUETEC uses a newly developed NOx adsorber, a catalytic device that converts NOx to nitrogen. Subsequent family members are slated to use urea-based injection system for NOx reduction. The adsorber has a lower conversion efficiency than the urea SCR systems.

Accordingly, the BLUETEC M-, R- and GL-Class vehicles will use the AdBlue urea SCR system.

Honda is developing a diesel engine and aftertreatment system that does not require the use of urea SCR to meet Bin 5 targets. The company has a target introduction of 2009. (Earlier post.)

CARB sucks. Diesel rules.

There - just wanted to get that out of the way. Now hopefully some meaningful comments can be made.

Not sure how many MB owners will feel that lower fuel cost helps offset the marquee status they dearly pay for. Don't want to suck much more NOX in Illinois.

FYI CO2 -

Both EPA and CARB define their emissions limits for vehicles, irrespective of the type of ICE used. Therefore, a Tier 2 Bin 5 diesel is just as clean wrt to each component as a Tier 2 Bin 5 gasoline vehicle, as measured by the standard certification tests.

Wrt ROI, compare the current E350 with the E320 cdi, which features a NOx store catalyst that meets Tier 2 Bin 6, i.e. it only narrowly failed CARB requirements. Vehicle performance is roughly comparable, the MSRP for the diesel is $500 higher. The gasoline model is supposed to be pampered with premium unleaded, which costs about the same as diesel in the US: http://tonto.eia.doe.gov/dnav/pet/pet_pri_gnd_dcus_nus_w.htm Note: the gasoline model will almost certainly cope with regular gasoline as well, as the knock sensor will automatically retard the ignition to avoid damage to the engine. This will slightly reduce available power (prompting more aggressive use of the gas pedal to compensate) and slightly increase fuel consumption (thermodynamics are worse). You'll save less at the pump than you might expect. The gasoline variant is rated 19/26MPG, i.e. 22 combined, by the EPA. Based on experience, real-world mileage is about 15% worse for most cars, so figure ~19MPG. The corresponding numbers for the diesel are 27/37, 31.5 and ~27MPG. Note that a future SCR system will deliver slightly better fuel mileage but also require additive refills, for consumer applications that's more or less a wash in dollar terms. In other words, you can reasonably expect the diesel model to travel up to 40% further on a gallon of fuel and, spend perhaps 1/3 less on fuel, oil, engine service etc. per mile traveled. You will also be emitting ~25% less CO2 per mile. At current fuel prices, the ROI for the$500 MSRP premium works out to ~12500 miles, i.e. roughly one year of operation. Sounds like a no-brainer to me.

Of course, if diesel engines were to capture a significant slice of the total LDV market, including more affordable models from other brands, that horizon would lengthen as fuel prices adjust to changes in supply and demand. However, it takes a decade or so for the fleet to churn, so this would be a very gradual process.

Rafael, great overview. I own two diesels and think they are one good solution. Only comment - a large portion of crude oil can be made into either diesel or gasoline depending on its refining, so if diesel cars were to greatly increase in number I think you might actually see diesel prices fall and gasoline prices rise, counterintuitively. As oil deposits get tapped out and more heavy oil is taken to market, because it is relatively more difficult to make good gasoline out of heavy oil, the balance could tilt even further in 5-10 years.

Zach -

you could be right, only a detailed study could reveal the potential net effect of several countervailing effects on gasoline and diesel prices at the pump.

The US market is currently so heavily skewed toward gasoline that large quantities of pefectly good middle distillates have to be hydrocracked just to satisfy demand volume. The cracker residue, called light cycle oil, is a significant component of US diesel fuel. This is why its cetane number is lower than that of European diesel. Note that petrochemical installations such as hydrocrackers are typically amortized over 20 or 30 years, so refiners are loath to stop using them any sooner.

As it is, US refineries still have to import some finished gasoline to satisfy peak demand in summer. Moreover, much of the Eastern US seaboard uses heating oil (aka LCO) for space heating in winter.

In other words, you can reasonably expect the diesel model to travel up to 40% further on a gallon of fuel and, spend perhaps 1/3 less on fuel, oil, engine service etc. per mile traveled. You will also be emitting ~25% less CO2 per mile. At current fuel prices, the ROI for the $500 MSRP premium works out to ~12500 miles, i.e. roughly one year of operation. Sounds like a no-brainer to me. Except for the fact that you can go to Edmunds and see they have the TCO at 86 cents/mile for both vehicles - and that despite the advantage in fuel savings, they estimate that repairs and depreciation will be substantially more for the diesel than the gas vehicle. Also, though diesel prices may be somewhat equivalent to premium fuel prices, there's a high degree of regional variation in price spreads. Also, the MSRP differential is closer to$1,000, not $500. Found a great site with even more info, you may want to check it out if you are seriously considering one of these cars. They also have information on the new smart car coming to the US. http://www.emercedesbenz.com/Sep06/25_Mercedes_To_Debut_BLUETEC_Models_In_All_50_States_Starting_Calendar_Year_2008.html or www.emercedesbenz.com Is there a trick to copy URl from this web sight Rafael: Slightly higher fuel consumption using regular gasoline on premium-tuned engine, you referred to, is the case when engine management switches to entire low-octane fuel map when detonation is detected. Modern on-board computers use way more sophisticated logic, and retards ignition only at the moment when detonation begin to occur. That’s mean full throttle at least, which is pretty rare occasion here in N. America. Max power will be lower, but overall fuel consumption will not be noticeable affected.. At winter, rainy day, or at high elevation (like whole Colorado) detonation will not happen even on full throttle. Lower octane fuel in such engines is noticeably noisier, thought. As of savings associated with diesel cars, let me describe you the picture for Canada, where diesel cars are still sold. Disposable income for Canadians is lower, fuel is taxed higher, and average driving distance per car is larger then in US. Still penetration of diesel cars is very low. The only diesel car sold in quantities in Canada is VW Jetta (Bora). MSRP is 26 310$, fuel efficiency for 5-speed manual is 6/5 l/100km, the engine is 1.9 liter 100hp turbodiesel, which for 1.4 ton car is a not a lot. Gasoline Jetta with 2 liter 115 hp engine has MRSP of 24 750 $(1500$ difference), with 5-speed manual fuel efficiency is 10/7 l/100km. Taxes effectively converts Canadian dollars to US, so we can use these numbers for correct comparison. Considering that part of auto insurance depends on book value of the car, and also adding 5% financing interest, one have to drive A LOT to realize savings from more efficient diesel engine. But the real picture is much worse for diesel. Way more appealing Honda Civic with 5 speed AUTOMATIC transmission, 1.8 liter 140 hp engine, fuel efficiency of 8/6 l/100km (same as for 5-speed manual), and MRSP of 18 180$(8100$ less then diesel Jetta), makes choice of the buyer quite obvious.

The picture could change if more sophisticated diesel-powered cars will appear on Canadian market, but I suspect not dramatically.

BTW, gasoline engine requires less money on oil changes then diesel, and is maintenance-free for lifetime expectancy. Repairs on diesel are usually more expensive then on gasoline engine.

Diesel will still outpull the equivalent petrol variant in the mid range AND it will last a hell of a lot longer.

I don't "pull" anything with my vehicles and therefore have no need for a diesel. All trucks should have the option of a diesel (meeting EPA standards).

Only the highest end vehicles (BMW & Mercedes) have diesel variants that can outperform the gasoline equivalent in terms of acceleration.

i -

the MSRP differential was taken off MB's US web site. As for accelerated depreciation, that is mostly a function of the low liquidity of the second-hand diesel market and would improve if buyers opted/could opt for diesel more often. Diesel drivetrains are indeed more expensive to service but then again, if you do take good care of them, they tend to last a lot longer. If you drive a lot of miles or tend to hang on to your vehicle for more than a decade, the economics are definitely in diesel's favor.

Andrey -

my discussion was limited to the MB models. You're quite right to point out that the economics are not as favorable for smaller, cheaper cars. Since both Canada and the US quite sensibly levy excise duty roughly in line with energy content, the break-even point lies further toward larger, heavier and more expensive vehicles than it does in the EU, where even the smart is available with a diesel.

Patrick -

diesel should indeed be at least an option on all pick-up trucks and SUVs sold in the US. Hopefully, carmakers will succeed in clearing the LDV emissions hurdles in the next few years.

I'm a little confused. Where is it coming from that diesels are more expensive to own/service? My friend has a Jetta diesel and he only has to change the oil every 10,000 miles. If he uses top shelf oil he can go 15,000 miles easy. He's had samples tested at Blackstone Labs which show that even his 15,000 sample could have been used for a lot longer. He doesn't have spark plugs to change. It also seems reasonable that since the engine works at much lower RPMs than a gas engine, wear and tear is much less.

I guess its also true that diesels tend to last three times longer than gasoline versions, but I guess the rest of the car better be up to snuff in order to last that long too.

So can you guys fill me in on what I'm missing?

John C. -

you make good points. The discussion referred to spare parts without explicitly mentioning that. In particular, all components of the fuel pressurization and injection system are much more expensive than their gasoline counterparts. Fortunately, failures are rare - though Bosch has not cleared biodiesel in vehicles that incorporate its unit injectors, because of a small risk of accelerated wear and tear on the nozzles.

John:
Iridium-tipped spark plugs (12$each, I changed for them my both vehicles), for example factory-fitted to my friend’s 3-year-old Corolla, have useful life of 190 000 km. High tension wires last approximately the same, and there is no distributor in modern engines. Practically nothing to maintain. Diesel engine requires more frequent oil changes due to oil contamination by carbon particles then gasoline one. Oil filter is bigger for that same reason too. On modern gasoline cars there are no fuel filter. Air filter on diesel is bigger too. Diesel engine is subject to way higher stress due to higher compression ratio and violent detonation (ignition delay, since the noise). Wear is higher on diesel too, especially due to presence of abrasive carbon particles in cylinders and lubricating oil. It is have to be built from better materials, with way more precise machining and heat treatment/coating to withstand this stresses, and this is the main reason of it higher cost and longer life. Well maintained gasoline engine easily lasts for 500 000 km; well maintained diesel – to 1000 000 km. It is critically important to commercial vehicles, but not relevant to passenger cars. As Rafael noticed, fuel system components are more expensive to repair/change, and in addition there is turbocharger, which is not cheap too. Andrey, But the Jetta diesel only requires oil changes every 10,000 miles, while the gas version requires it every 7000 miles or so. Why do you say the diesel needs to change the oil more often when you don't? Maybe this is just unique to VW? Please let me know as I keep getting conflicting information and viewpoints. I do know that my 2006 Sienna has a fuel filter. I'm pretty sure that all cars do. Please correct me if I'm wrong. I'll ask my friend how often he has to change his fuel filter. Not sure about comparing the oil and air filter size. I looked online and they look very similar to the gas versions and carry the same price tag within a few cents. Are you saying that the air filter usually needs to be replaced more often in a diesel? I'll ask my friend what his schedule says. I didn't realize the turbo thing or the possible costs of fuel system parts if they fail. I guess that after the usual 100,000 mile power train warranty runs out there could be some big expenses on the horizon. But can't that be said for any car of any type? Plenty of gasoline cars have turbos, and anything can go wrong after a lot of miles. But what about the basic longevity issue? I mean, if the gasoline engine will die in half the time of a diesel, isn't that the worst possible expense that can occur? So maybe the diesel will have some sub system issues after a long time, but you won't have to replace the entire engine and possibly the drive-train like you would with a gasoline car. Again, this is just my current view based on what I've learned. Please fill me in on any gaps you find as I just want to learn all I can. John: What I described is general maintenance considerations, applied to diesel vis gasoline engines. Differences between models and manufacturers vary widely. Filters are peanuts and are not really costly and important. Couple of things are: Turbocharger is capricious and expensive item on both gasoline and diesel. Diesel engines just have them way more often, and modern diesels are universally turbocharged. As I said, well maintained gas engine could last untouched for 300 000 miles. Diesel – 600 000 miles. For most drivers 300K is more then enough. Gasoline engine is as easily overhauled as diesel, but because there are plenty of factory restored or simply low-mileage engines from scrap-yards, it is cheaper just to swap them. Repair of fuel system (high pressure injectors and fuel pump) for diesel costs major bucks, and their failure/contamination in not that uncommon. Lubrication oil analysis reveals how basic oil stock is holding. However, modern oils carry amazingly effective package of friction modifiers, detergents, corrosion inhibitors, etc. On diesel engines these additives are adsorbed by carbon particles accumulating in oil filter, and wears out faster then on gasoline engine. This is the reason why synthetic oils benefit diesel engines less then gasoline ones – oil is OK, it is additives who wears out. Commercial vehicles maintain this additive package by periodic addition of special concentrated oil conditioners, and I have read even about special cartridges which are inserted in oil system and slowly release replenishing additives. My suggestion is do not exceed oil change intervals even if oil looks OK. Some drivers add oil additives at half oil life, but some of additives are dangerous to engine (especially with graphite and Teflon particles), and costs money. Better way is just change oil more frequently. Andrey, thanks for the information. Seems to make sense, although for my friend's VW, the oil seems to be lasting much longer than factory spec. Factory says to change every 10,000, but he's done it at 15,000 and sent samples to be tested. The results showed the additives still very high so he could have gone longer. Maybe just a model specific thing. Boy I hope my Sienna lasts 300,000 miles. I am very careful about taking care of my cars and I've never had one last much past 200,000 before all sorts of things started to go wrong. Andrey hates diesels...no matter if they now meet CARB emissions or are cheaper to maintain. Having been in the auto repair biz for 20 years driving 99+% gasoline cars, most w/turbos...and now driving my first turbodiesel car since new...I know why NA auto dosent want TDs over here. They dont break(no ignition system...priceless), maintenance is a breeze (and Im changing Mobil1 every 5K just becuz) and with cleaner, higher cetane fuel(ULSD,bioD,FT) arriving Im sure it will get even better. Diesels arent for everyone. But hard-driven daily use/commercial vehicles putting over 50+ mpd need this option. E85 and H2 hoax needs exposure. Andrey hates diesels...no matter if they now meet CARB emissions Which diesel light vehicles are for sale in California? All gasoline engines I have seen contain two fuel filters. One is really just to get large particles out of the pump and is more like a "sock". The second is an actual filter. Modern gasoline engines have distributorless ignitions (as indicated above by Andrey) with either coil pack or coil on plug arrangements and these solid state components will last as long as the engine. Maintenance is just as easy on gasoline engines. Most new vehicles are rated 15,000 miles between oil changes and 100,000 miles between sparkplug and O2 sensor changes. High temperatures in the turbo (gas or diesel) can destroy non-synthetic oil quite readily if given the chance [for those who may not be aware: turbos use a high pressure oil line off the engine for lubrication of the center cartridge/bearing and cooling unless you also have coolant lines plumbed into the turbo] Andrey: Modern synth oils take care of soot build up no problem. Modern diesels have very low in-cylinder soot to begin with. My 1998 TDI has gone 17000miles on Mobil Delvac 1 (the guy using Mobil 1 - that's not really for diesels), consuming about 1/2qt/5000miles (4qt sump). Oil analysis showed the oil was suitable for continued use - 20kmi not dangerous, in my application (30/70 cty/hwy, temperate climate). The main difference in cost comes from the more precisely built fuel system, not so much from beefing up the engine block. While wear due strictly to lube contamination may be higher with the diesel, overall wear is lower (and longevity greater) primarly due to lower revs. "Well maintained" gas engines may last 500kmi, and diesel 1mil, but when considering "typically maintained" then it DOES make a difference to the "average" driver, especially come resale time. John: I am big fan of Mobil1 too. Fred: H2 and E85 hoax got a lot of exposure on this blog. I do not hate diesel. I worked in emission reduction R&D for big diesels. For cargo hauling/towing diesel is a must, and I wrote it before many times. Family sedan putting 15K miles a year does not benefit from diesel. Hard driven car (50K miles per year) – I am not sure. At least taxi drivers, couriers, and even pizza delivery always preferred gasoline (small Japanese, when possible). Agree? Patrick: I believe that Honda moved to filter-less gasoline system. And I do not like it. "Hard driven car (50K miles per year) - I am not sure." FYI, you cannot say that and possibly be taken seriously. My point was 50mpd was the extreme low end. When I see property taxes up 7% per year here in Chicago, and pension funds under-funded, and cops and cabs drivin their Police Interceptors around like NASCAR, fillin up twice a day maybe getting 10mpg...35-45mpg out of a turboD makes a shitload of sense no? Sadly other than VW there are few diesel options, and 6.6 Duramax and$50K+MBs arent. This game-playing between our nannies (CARB,EPA,DOT) and the automfgs over 1/100s g/m NOx has got to stop ASAP.

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