2014 2.0L Turbo Diesel Cruze is here!

[cRiPpLe_rOoStEr]

Originally Posted by tjts1

The SCR makes the engine more fuel efficient compared to periodically dumping fuel into the exhaust to regenerate the DPF.

But the DPF is still there, alongside the SCR.

[tjts1]

Originally Posted by cRiPpLe_rOoStEr

But the DPF is still there, alongside the SCR.

Yes and the SRC is there to clean out the DPF so you don't have dump extra fuel into the exhaust to burn out the soot.


Jetta without SCR
Fuel Economy of the 2013 Volkswagen Jetta

Passat with SCR. Bigger car, same engine, same transmission.
Fuel Economy of the 2013 Volkswagen Passat

[niky]

The good parts:
-The diesel is a willing engine, and Chevrolet's European diesels are based on sturdier stuff than the Japanese. Typically Korean cars (let's be honest... can't get much more Korean than the Cruze) have good diesels, with most fuel systems lasting into the 100,000+++ mile range with no major problems.

-The Cruze is still a good platform. Nice legroom. Incredibly refined.

The bad parts:
-Yes... the economy of the 2.0 isn't that great. I drove one and topped out at about 45 mpg on the highway. I say it's not that great because a TDCI Focus with the dual clutch can get near-50.

-And... ugh. That six speed automatic. It's got the same damnable transmission logic that makes driving the regular Cruze so irritating. Drove one on the racetrack last year. Had to purposely miss the apexes so I could stay on throttle, otherwise I'd be stuck hanging there waiting for the transmission to downshift. Downshifts would add an extra second or two(!) to each corner exit. And no... left-foot braking doesn't help. If you slow down and need a downshift, you're stuck.

In the real world... that transmission makes the extra power of the diesel largely irrelevant. The "135 hp" Focus is more urgent at every speed than the "160 hp" Cruze. So you're not missing much, really, in the de-tuning.

[Diesel_Dave]

Originally Posted by tjts1

The SCR makes the engine more fuel efficient compared to periodically dumping fuel into the exhaust to regenerate the DPF. Thats why the US market Passat TDI with SCR is more fuel efficient than the Jetta TDI without.

DEF can be purchesed at any truck stop or Walmart for cheap. Its a non issue.

Not necessarily. SCR is for NOx emissions, DPF is for particualtes (soot). The Cruze has both devices. The SCR will use DEF and the DPF will still need periodic regens (burning extra fuel).

That being said, SCR can lead to fewer DPF regenerations indirectly. Engine-out NOx & particulates are often inversely related--more NOx = less soot, less NOx = more soot. Engines with SCR can afford to put out more engine-out NOx because the SCR will clean it up. As a result, typically there's less engine-out soot, and therefore the DPF won't require regens as frequently.

Although this wasn't done with the Cruze, I have seen some designs where manufactures have used SCR to eliminate the need for a DPF completely by running super-high engine-out NOx (& super-low engine-out PM). They let the SCR take care of the NOx and don't need a DPF. I know some European dieseln trucks met Euro 5 emissions this way. In Euro 6 the PM standard is a lot lower (pretty similar to what the US is now) so I'm not sure if there will be trucks without DPFs.

Now, as far as SCR increasing fuel efficiency, that can be partly because of the fewer DPF regens. Also, engine-out NOx and fuel efficiency are often directly related (more NOx = more efficiency). For that reason, engines with SCR can often run more efficiently than non-SCR engines--they're tuned primarily for efficiency (rather than low NOx) and the SCR cleans up the NOx after the fact. Look at the semi trucks with Navistar engines the last few years. All the other manufacturers went with SCR systems, while Navistar chose to avoid SCR and run low engine-out NOx by running lots of EGR. That decision has nearly bankrupted Navistar because their engine had awful efficiency and effentually they couldn't meet the emissions standards at all without SCR.

As far as the cost of DEF goes, I wouldn't call it "cheap". It's typically less than diesel, but still a couple bucks a gallon.

[cRiPpLe_rOoStEr]

A good car with a badly-tuned engine

[tjts1]

No, its a below average car with an awful price tag. Its $2000 more expensive than the Jetta TDI (main competitor in the US market) $5000 more expensive than the 1.4eco which gets the same fuel economy numbers,$2000 more expensive than the Prius lift back which has much lower cost per mile and it burns diesel fuel which is 20% more expensive than gasoline in most of the US. Unfortunately for diesels, in most of America hybrids and small displacement gasoline engines are cheaper to both buy and fuel. I doubt GM will offer this engine in the US 2 years from now. I think they setup this diesel to fail.

[trooper Tdiesel]

id bet that yanking all that junk would get it up to around 60+ mpg with a auto trans.
sooner or later some one will do it....

i love my old school diesels

[cRiPpLe_rOoStEr]

Originally Posted by trooper Tdiesel

id bet that yanking all that junk would get it up to around 60+ mpg with a auto trans.
sooner or later some one will do it....

60MPG in highway sound more reasonable to achieve with a manual transmission, even after all the emissions deletes.

i love my old school diesels

There is no school like the old school

[mechman600]

Originally Posted by trooper Tdiesel

id bet that yanking all that junk would get it up to around 60+ mpg with a auto trans.

Not to mention making it reliable. Aftertreatment systems are the number one reliability issue in modern diesels. Just ask a trucker who owns a 2007+ product.

However, aftertreatment is a necessary evil. Old school diesels spew out biblical amounts of poison from their tail pipes and they stink, at least in comparison to their gasoline powered counterparts.

In the early 70's, people complained about emissions non-stop. Lots of emissions devices were removed to make cars reliable/driveable. But look at cars now: more powerful and cleaner than ever before, and nobody even thinks about emission devices anymore. Now diesels are going through the same thing as gasoline cars in the early 70's. I bet in 15 years we probably won't even think about it anymore.

[PressEnter[]]

Just personal preference, but with no manual, I'm not interested.