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Chrysler to Offer First Mid-Size Sedan Diesel with 2007 Sebring; Only Outside of North America

The 2007 Sebring

Chrysler is introducing its all-new 2007 Sebring with a 2.0-liter turbo diesel engine for key diesel markets outside North America. This is Chrysler’s first mid-size sedan diesel offering.

Models of the 2007 Sebring sold in North America have a choice of three gasoline engines: the new 2.4-liter four-cylinder World Engine, a 2.7-liter V-6 engine and an available 3.5-liter V-6 engine coupled with a new six-speed automatic transaxle with Auto Stick.

The diesel engine will deliver an estimated 140 horsepower (103 kW) and 236 lb-ft (320 Nm) of torque.

Coupled to a four-speed automatic transaxle, the standard 2.4-liter World Engine provides a 15% increase in horsepower (172 hp (128 kW) vs. 150 hp (112 kW)) and 4% improvement in fuel economy compared with the 2.4-liter engine it replaces. The engine develops 165 lb-ft (222 Nm) of torque, and offer estimated fuel economy of 23 mpg city, 31 mpg highway.

The available 2.7-liter V-6 engine produces 190 hp (142 kW) and 190 lb-ft (258 Nm) of torque, providing more low-end torque (at an rpm 850 lower) compared with the 2.7-liter engine it replaces. Fuel economy is an estimated 22 mpg city, 29 mpg highway.

Chrysler Sebring sedans sold in the United States are also available with 3.5-liter V-6 engines that produce 235 hp (175 kW) and 232 lb-ft (315 Nm) of torque coupled with a new six-speed automatic transaxle that comes standard with Auto Stick. Fuel economy is an estimated 19 mpg city, 28 mpg highway.

The 2007 Chrysler Sebring is one of the first Chrysler Group vehicles to offer the new six-speed automatic transaxle.

The 2007 Chrysler Sebring will be available in US dealerships in the fourth quarter of 2006 and in global volume markets in the first half of 2007.

2007 Chrysler Sebring
Fuel Gasoline Gasoline Gasoline Diesel
Power hp (kw) 172 (128) 190 (142) 235 (175) 140 (103)
Torque lb-ft (Nm) 165 (222) 190 (258) 232 (315) 236 (320)
Fuel economy
(city/highway mpg US)
23/31 22/29 19/28 n.a.


Bud Johns

Why not OFFER the Diesel in the US????? And what's with using 4 speeds with the smaller, less powerful engines, but a 6 speed with the most powerful ones??

allen zheng

Come on, a four speed?! The spread of design and tech from Benz to Chrysler has got to be better. A clean diesel Chrysler/Dodge/Jeep for 2009 US should a priority for DaimlerChrysler. The high(Benz)/medium(Chrysler)/low -> lightweight(Smart)/mid-weight/heavyweight -> car/ crossover/truck punch they got available for clean diesel and hybrid conversion could steal the thunder from Toyota/Honda.
Note: They got the hybrid tech developed with GM, they got Blue Tech diesel, and lightweight superstrong composite construction coming online.

Rafael Seidl

Bud -

the engine cannot meet US emissions. I suggest you direct your fire at those who decided that CO2 is not a pollutant that EPA and CARB are permitted to set limits on. Not being responsible for fuel economy means they don't much care if their regulations reduce it. To its credit, CARB is trying to limit CO2 but the auto industry immediately sued them because that has hitherto been the preserve of the federal Dept. of Transport.

Elsewhere, e.g. in Europe and Japan, a single agency is responsible for both fuel economy and noxious emissions.

Wrt the gear number: smaller engine, cheaper car, lower comfort requirement, lower top speed => cheap transmission. Bigger engine, more expensive car, higher comfort requirement, higher top speed => more gears.

It's not clear which transmission the inline 4 diesel will be offered with in Europe. Most competitors rely on 5 or 6 speed manuals and offer an AT as an upgrade option. Note that the 2.0L turbodiesel produces as much torque as the 3.5L naturally aspirated engine, probably at much lower RPM. Maximum power is lower, but how often do you actually operate an engine at full throttle on any passenger car?

Bud Johns

Rafael, right you are on all counts. The impossibly difficult diesel emissions here should be revoked. No suprise about the torque matching the much larger gas engine at lower rpm, turbos and diesels go together like peas and carrots....not to brag or anything but my Prius' electric motor puts out 295 lb/ft from zero rpm!

Rafael Seidl

Bud -

and that is why combining a diesel with an electric motor would give you more torque than your wheels would know what to do with (unless you have mechanical or electrric AWD or, a RWD commercial vehicle with heavy paylod).

EPA & CARB would get drawn and quartered in the courts if they stepped back from ever-more stringent emissions regs, unless Congress decide to redefine their charter.


What about a small turbocharged diesel hybrid?


One liter or less. Two cylinder opposed. Two cycle, air cooled.

John Ard

It sounds to me like Lucas wants a diesel VW bug. Ever heard of the Screaming Detroit? Back when over-the-road (Class 8 to ya'll) trucks still had 2-cycles they were hated for their lack of low-end torque and the neccesary standing on the gas (diesel?) pedal to go anywhere (hence the screaming). I don't know much about modern 2-cycles, but I had to chuckle a little when I saw one suggested for a new Chrysler. Someone enlighten me on the subject. :)

Bud Johns

I assume he's baiting people. Can't be serious. It would be super loud, and the air cooling would make it even louder and tolerances couldn't be as close. Lastly, it would have to have a blower, they won't even run with a turbo until the exhaust reaches a high enough temp. Lots of weight, etc. That's how EMD and detroits used to be set up. Four strokes have taken over in everything except the ultra massive ship engines.

Rafael Seidl

Lucas -

you're actually not as far wide of the mark as John and Bud suggest. Back in the 90s there was considerable interest in reviving the two-stroke concept for automobiles. Orbital in Austrailia, AVL in Austria and Daihatsu in Japan all presented 2 or 3 cylinder engines with around 1L displacement. The AVL design was a watercooled diesel with 4 exhaust valves per cylinder and a turbo, topping out at 58kW @ 3500 RPM. The trouble is that by the time you meet emissions regs, a two-stroke is just as complicated (or more so) as a four-stroke, and no longer all that much lighter.

However, don't give up on the old two-stroke diesel just yet. Because there are twice as many combustion events, you can get the same power level at a lower load. Theoretically, this would allow you to apply HCCI combustion in virtually the whole engine map, reducing NOx and PM emissions by 80% or more. The combustion noise would be pretty deafening, though, making even more extensive acoustic encapsulation neccessary. Also, the engine just as heavy and expensive as a four-stroke of the same displacement (or more so). On the upside, you could meet emissions regs without expensive lean-burn NOx aftertreatment.

For larger displacements, you would want at least 4 cylinders or inertial compensation.


There is another possible niche in which a two-stroke diesel might yet play a role: opposed piston engines for (drone) aircraft.

New variants of this very old design concept have recently been proposed by FEV and commercialized (for military apps) by APT:


Check out the video with the golf ball on the running engine. Note that the inside cylinders do not have a cylinder pin but rather a sliding support. This virtually elongates the inner conrods, reducing laterals forces on the piston rings and skirt and, reducing overall build length. Only works if you can keep in-calnder pressure above (atmospheric) pressure in the crankcase, though, hence the electrically assisted turbocharger. Forget about the 6-cylinder variant intended for automotive use. 12 pistons for 40kW is just way too expensive.

Another company proposing opposed-pistons designs for small aircraft is Golle AG (site is in German):


The big issue with opposed-piston designs is the high temperature of the exhaust slits, causing engine oil to coke up. HC emissions also remain a problem (blue smoke), unless you shell out beaucoup $$$ for dry friction bearings as Golle is proposing. Life expectancy is another unsolved problem.

allen zheng

2 cycle diesels of 10,000 kw or more can get close to 50% efficiency. They are mostly ship engines and large emergency backups, but may be modified to run on other fuels(natural gas)/fuel mixes(biodiesel-ethanol-hydrogen).

Bud Johns

This website will tell you about the world's most powerful diesel, complete with mind-boggling photos. Highly recommended. http://www.bath.ac.uk/~ccsshb/12cyl/

Dave Zeller

In all fairness, the two-cycle GM Detroit Diesels really weren't a bad engine. When introduced in 1937 they were able to run at least 350,000 miles before maybe requiring top-end overhaul, and Greyhound Bus Line wouldn't retire a bus until it had 850,000 miles on it. At this time, you couldn't get more than 35,000 miles out of a gasoline engine before it required a valve job or worse.

Also, the GM buses from the late '40s and early '50s when setup with the 4-71 engine could easily get 10 m.p.g.
Today, a modern bus with similar passenger capacity is hard pressed to get over 1.6 m.p.g., and the hybrid units struggle to achieve 2 m.p.g.


Dave- One important factor with the comparison of buses from the early 40's & 50's versus modern buses: Pollution.

Bud Johns

Dave, a 4-71 means 4 cylinders at 71 cubes apiece. 284 inches of diesel wouldn't even come close to powering a bus, and none of them were turbo then. They did have 6-71's back then, but still.......(They eventually had v-8 and v-12-71s, and with turbos feeding the roots blowers, they were quite powerful). As far as blowing away today's fuel consumption by a factor of nearly 10, come on man!


Lucas, the engine you want is already built. It's the OPOC


Dave Zeller

Before saying that the GM 4-71 could never power a bus, and doubting the fuel economy potential over modern buses, you may want to look at this:




(The Russian ZIS 154 had a Russian license-built 4-71 set up with a unique, but inefficient, electric drive system which DID NOT get anywhere near 10 m.p.g.; however, it could still manage around 5.88 mpg, over twice the economy of the best hybrid buses built today!)

The GM 4-71 and 6-71 are still built today in Russia at the plant we gave them, under Lend-Lease, in 1947.
(They are known today as the YAZ-204 and YAZ-206 series)



ZIS 154: 8000kg, max loaded speed of 65km/h (40mph)

New Flyer D30LF: 11110kg, max speed??? couldn't find the information but we don't seem to have any problem with them doing 70mph on the interstate highways around here.

Now factor in the HVAC on the newer buses (none on the older) and pollution controls and consider that I did not find ANY information on a bus with the 4-71 engine achieving greater than 5.9mpg and most references in general to modern buses put their fuel economy in the 1.3 to 3.8 mpg range depending on drive cycle used and it seems that the old engine isn't so magically delicious after all.

Dave Zeller

City buses only need to go about 40 m.p.h.; of course, highway units will go faster, at least 60 m.p.h.
Uh, couldn't find any information on ones able to get more than 5.9 m.p.g., and supposedly without airconditioning?


"All PD 33 and 37 series models with the letter "A" were air-conditioned" (early 1940s!) and "very economical buses with 10+ MPG common with the 4 cylinder diesel engines. Top speed was almost 60 MPH at 2150 RPMs, but with the "4 banger" engine they died on any hills they climbed."

60 m.p.h.? I remember that not too many years ago in my state, the police would write you a ticket if they clocked you 5 m.p.h. over the 55 limit, so speed really isn't an issue, either.

(Sigh!) Pollution controls have absolutely killed ANY chance of getting decent fuel economy in modern road diesels, as Our Wise Environmentalists at the E.P.A. have mandated that NOX levels be reduced, which can only be done by making the engines run hotter (retarding the injection timing, where you basically make the engine work against itself). I don't know what to do about that one, but that's what happens when you have government mandarins telling engineers how to design diesel engines.


Welcome to Bus Talk!
OK so theyre built in Canada i guess? and they(diesels)cant be sold there because? And Mexico. Do they have any emissions specs? So the "No diesel cars in NA" saga trudges on.

Rafael Seidl

Dave -

fyi, modern diesels use multiple injections to shape combustion noise and NOx emissions. In part load, they use cooled external EGR to reduce the rate of heat release.

In general, NO is only produced in significant amounts above 2000 deg K. The innocuous NO is converted to the smog-forming NO2 partly within the engine but mostly under the influence of sunlight in the atmosphere. That is why the NO mass measured during vehicle certification tests is used to compute an equivalent NO2 mass.

Reducing engine-out NOx emissions (= tailpipe NOx in diesels w/o NOx aftertreatment) requries a redution in the peak temperatures that occur in the flame front. Late injection achieves this by igniting more of the fuel when the piston is already well past TDC, thereby limiting peak chamber pressure. The downside is reduced thermodynamic efficiency (i.e. higher fuel consumption), which is only partly compensated by the higher exhaust enthalpy available to the turbocharger.


Trucks are running today in europe using SCR and "Adblue", a 40% Urea and water solution. They meet those "impossible " to meet regulations we have here in the US for diesels. Type in "find adblue" and you can find a station in London if you need one.
We can use this technology for trucks after we get ULSD this fall. The goal is to get the Urea usage down so it can be replaced at the same time as the oil during routine changes. They are not there now and you have to add @5% of fuel volume. 5 gallons per hundred. The stuff is about the same price as fuel here, but fuel economy goes Up since the EGR, timing and other ICE kludges are eliminated. It is about a wash except for the major problem of the infrastructure set up!
The pollution goes down dramaticly.
I get my emissions info from Dieselnet but I'll let other say what the reduction is over the current US truck regs. It is so much that anyone fighting it has NO clue what environmental engineering is all about. Best Availible Control Technology.

Richard C Burton

I recall the 2 stroke GM diesel buses well from their extensive use in my home town of San Diego in the 1950's. They were horribly noisy and dirty, using a 2 speed auto trans, that was full torque converter in first(thus peak revs from zero mph), then clunked into a lockup top gear at about 25mph. I often thought they were made dirty and noisy to discourage the use of public transport, and hence more car sales for GM(who had apparently already bought up, and torn down, the trolley system).The ones in San Diego used open windows for air conditioning...they did seem reliable tho, and I can't recall ever being stranded on one.


Regarding the mileage claims for old buses (10 mpg): yes, some of the old 4-71 and 6-71 powered buses did get up to that, but only in over the road use (meaning 45-55mph). The comparison to current buses getting 1.6 or 2 mpg are by city transit buses, which is constant start and stop driving. I remember hearing that the 6-71 powered city buses were getting 2 to 3 mpg. And they were lighter and simpler. Also, the over the road buses had a seperate diesel-powered AC unit, not run off the main engine, until the 8-71 PD4106 came along. And yes, the acceleration and hill climbing powere would be dangerous in today's traffic. That's why all buses and trucks have 2 to 3 times the HP, to keep up with traffic, especially on hills. Life, and traffic was slower paced back then.


What forced busses and cars to get more power was overcrowding of the roads, poor road design, and a massive increase in the number of 18 wheelers on he road.

It didnt matter if you were slow in 1960. In 1980 it mattered a fair bit as often many merge lanes were 1.3rd the length old lanes were and the roads had far more people and heavy trucks on em...

Now... its insane. Roads that became dnagerously crowded in 1980 have yet to be expanded.. routes that were overcrowded in the 80s still have no laternate routes... And yet more trucks on the road...

Where I live everyone commutes with the 18 wheelers and other BIG trucks every day. You only have to drive by one small car vs multiple semis accident to never drive one ever again.

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