Drove the new Chevy Cruze diesel yesterday

[begreen]

Not really DIY, but I had an opportunity to test drive a new Chevy Cruze diesel yesterday. It is a gutsy powerplant, but it takes a bit of adjusting to get used to the turbo kicking in. I felt its punch a couple seconds after pulling away from a light. There is power to spare even with the additional diesel weight. The car is quite nice, but the noisy diesel surprised me. I was expecting something more sophisticated like the VW TDI engine. Instead the clatter and rattle was quite apparent from the outside. Inside the car they have done a very good job of sound proofing so it is not too bad, except when you punch it or go uphill. To be fair we were comparing it to the very quiet Volt so our ears were sensitive to the noise.

It will be interesting to see how this one sells. With a light foot mileage should be very good. I found on the highway it was getting over 50mpg.

 

[Jags]

That is pretty neat.
I am starting to get excited about the new players in the diesel market. Jeep finally decided to try again (previously there was a year that the grand Cherokee used the Mercedes blue tech).
What the heck - 30 mpg highway is a bunch better than the 18-20 currently offered. AND they retained the hauling capacity. 420 ft/lb of torque is nothing to sneeze at.

"The 2014 Jeep Grand Cherokee gets an available 3.0-liter turbodiesel V-6 produced by VM Motori (co-owned by Fiat and GM). The engine will produce 240 hp, 420 lb-ft or torque, while achieving 30 mpg highway (good for a 720-mile range). The new diesel, rated to tow 7400 pounds, uses urea after-treatment and a diesel particulate filter to meet emissions standards."

Heck - a TBI chevy 350 only puts out 300 ft/lbs. And a 454 TBI is at 385.

 

[Highbeam]

Cool. Looking forward to more acceptance of that rattle.

Diesel prices are plummeting here in the NW to 3.75$. Almost matching gasoline prices at 3.70$. Often, the higher price for diesel has eaten up some of the cost savings of higher mpg.

In the pickup world, I drive this ridiculous F350 diesel to work every day since it gets mid teens mpg city and 20+ freeway. I do NOT need an F350 very often but there is no other option. The technology and public acceptance of diesel will only encourage the diesel tech to spill over into pickups.

 

[SIERRADMAX]

I love diesels. I own a diesel pick-up and while shopping around for a new car for the wife, I wanted to get a diesel. With the amount of international traveling I do, almost every other country has "stripped down, no-frills" diesel sedans. Here in the US, if you want to purchase a sedan or SUV with a diesel, almost all manufacturers only offer the diesel in a "premium package". For instance. VW jetta 2.0L gas $17k MSRP, Diesel $23k. Cruze LS $18k MSRP, diesel $26k.

 

[semipro]

I'm thinking diesel/electric hybrids might be a good option.
I believe diesel cycle engines operate more efficiently when designed to operate within a narrower range of RPMs, like the Atkinson Cycles gas engines used in the Prius.
I also like the potential for bio-fuels use in such hybrids.

 

[sam-tip]

My 2007 Diesel Jeep Grand Cherokee gets 21 to 24 mpg with full time 4 x4. It has plenty of get up and go. The new 2014 will have an 8 speed transmition. It is still the quietest diesel I know of. No clattering.

 

[Jags]

My 2007 Diesel Jeep Grand Cherokee gets 21 to 24 mpg with full time 4 x4. It has plenty of get up and go. The new 2014 will have an 8 speed transmition. It is still the quietest diesel I know of. No clattering.

That was the Mercedes Blue Tech diesel. Quite a motor in its own right. The 2014 will be using a 3.0 liter turbo diesel and is reported to turn out 30 MPG highway.

 

[maverick06]

I have a 1999 jetta TDI. I have 179k miles on it and am getting about 53mpg. Its a very solid car, it has it's problems, but nothing too unpleasnt. certainly hard to argue the fuel milage.

 

[jharkin]

I'm thinking diesel/electric hybrids might be a good option.
I believe diesel cycle engines operate more efficiently when designed to operate within a narrower range of RPMs, like the Atkinson Cycles gas engines used in the Prius.
I also like the potential for bio-fuels use in such hybrids.

I had wondered the same, especially since this is a proven combination giong back 50 years or more in locomotives.

From what I read, there are a couple reasons its not done:

#1 - cost
Diesels are already more expensive to build than gas engines, and so is a hybrid. Put the two together and the cost premium wouldn't sell.

#2 - Combined efficiency
Gasoline engines are least efficient under low rpm / low throttle operation due to pumping losses. So in a hybrid you let the electric do most of the work around town (when gas is least efficient), and use the gas engine mostly at high speed where its operating at medium-wide open throttle under load and most efficient.

The diesel with no throttle losses doesn't loose as much efficiency at low speed and thus doesn't benefit as much from electric assist (other than the regenerative braking).

 

[lukem]

Somebody please, PLEASE, give me a diesel in a truck in something less than a 3/4 ton wrapper. I'd gladly trade the ability to tow 12K+ for some extra MPGs.

Edit...I guess they are coming out with one this year. Too bad it is a Dodge.

 

[TMonter]

I'm thinking diesel/electric hybrids might be a good option.
I believe diesel cycle engines operate more efficiently when designed to operate within a narrower range of RPMs, like the Atkinson Cycles gas engines used in the Prius.
I also like the potential for bio-fuels use in such hybrids.

Diesels have a better brake specific fuel consumption mainly because of the higher compression ratio. The narrower RPM range is a natural effect of the type of fuel burned which has a much slower flame front speed than gasoline.

Really the biggest reason we don't have diesels here in the US is primarily because of EPA regs. They sell them all over the place in Europe.

 

[Highbeam]

Diesels have a better brake specific fuel consumption mainly because of the higher compression ratio. The narrower RPM range is a natural effect of the type of fuel burned which has a much slower flame front speed than gasoline.

Really the biggest reason we don't have diesels here in the US is primarily because of EPA regs. They sell them all over the place in Europe.

Having driven a modern turbo diesel and even my non-turbo tractor, I have found that the operating RPM range is not narrow. It is quite wide, much wider than seems to be being portrayed here. Power off the line at just over idle all the way to redline at nearly 4000. The gas engine has a wider range, like twice as wide but you need to be at high rpm to get a significant amount of power. This is the part where you just have to drive one to understand. The torque curve of a diesel is flat and not peaky like a gas engine so the rpm range is not as important

Remember folks, we are seeing 8 speed automatic transmissions and within those 8 gears you also have the torque converter locking and unlocking. The rpm of the engine can be very narrow and still get brisk acceleration.

How long before the colorado pickup comes out with the same diesel as the cruze?

 

[TMonter]

Having driven a modern turbo diesel and even my non-turbo tractor, I have found that the operating RPM range is not narrow. It is quite wide, much wider than seems to be being portrayed here. Power off the line at just over idle all the way to redline at nearly 4000. The gas engine has a wider range, like twice as wide but you need to be at high rpm to get a significant amount of power. This is the part where you just have to drive one to understand. The torque curve of a diesel is flat and not peaky like a gas engine so the rpm range is not as important

Remember folks, we are seeing 8 speed automatic transmissions and within those 8 gears you also have the torque converter locking and unlocking. The rpm of the engine can be very narrow and still get brisk acceleration.

How long before the colorado pickup comes out with the same diesel as the cruze?

Diesels certainly have a flatter torque curve but like I said the narrower rpm range is an effect of the fuel, not the engine itself. Diesels lend themselves well to a lot of straight line steady state driving or towing because of the high torque but have lower power density per unit displacement.

As for the 8-speed transmissions I'm not sold on those yet when it comes to long term reliability and cost of repair. I like the idea but what are they really like when you get 10-15 years down the road?

 

[jharkin]

You can make a flat torque curve in a gas engine too - that's what variable valve timing is so great for, being able to have different cam profiles to eliminate the peaky power delivery. In a gas engine a flat torque curve feels "peaky" as you drive it because horesepower just keeps building to redline.

Lets look at an example, comparing 2.0 L inline 4 gas and diesel engines.


Gasoline
Since I'm familiar with it from my car, lets use the Honda 2.0L naturally aspirated K20A2 engine (just look at the "stock" lines). It makes a pretty uniform 110-120 ft lb from 2500 all the way to fuel cutoff at 8200 rpm. This is at the wheels.

Diesel

Same size diesel would be the Jetta 2.0 TDI. The dyno below is a stock 2009 VW 2.0 TDI. dotted line is torque.

This diesel makes much more peak torque (over 210 at the wheels vs 120) but less HP (~135 vs ~160 at wheels). The biggest difference is that it has really usable torque right off idle, whereas the gas engine is weak under 2500 rpm.

In this comparison in fact the Diesel has the peakier torque curve but since its peak is so low and the absolute torque is higher it would be easier to live with & drive and feel more powerful (nearly twice as powerful) to the typical driver who short shifts under 3000rpm. If you are willing to drive it like a race car (shifting to stay between 5000-7500) the gas engined RSX is a much faster car.

In reality what you are feeling as a "flatter torque curve" in the diesel is really a flatter horsepower delivery. The gas engine has a peakier horsepower delivery and thus has to be driven harder to feel powerful.

 

[ironpony]

I agree with the EPA statement, we should have 60mpg diesels all over the place. EX; I have owned several pre 2004 Dodge Cummins, all of them are in the 20mpg range. full size extended cab long bed 4X4, 300 plus horse power 500 plus foot pound of torque. After 2004 EPA changed the rules, fuel mile has rapidly decreased, maintenance has increased and some trucks have to add urea to have clean emissions at added cost. cleaner emissions but half the fuel mileage, where is the savings?

I sold my newer Cummins with all the computer crap and low mileage and went back to a 2002 with 20mpg, now its not all that but a 8000 pound truck getting 20mpg that can move a house is pretty impressive. And to rebuke the statement the light duty diesel made by Dodge, if it has a Cummins 4BT series engine in it, it will run for 400000 miles.

 

[pyroholic]

You can make a flat torque curve in a gas engine too - that's what variable valve timing is so great for, being able to have different cam profiles to eliminate the peaky power delivery. In a gas engine a flat torque curve feels "peaky" as you drive it because horesepower just keeps building to redline.

Lets look at an example, comparing 2.0 L inline 4 gas and diesel engines.


Gasoline
Since I'm familiar with it from my car, lets use the Honda 2.0L naturally aspirated K20A2 engine (just look at the "stock" lines). It makes a pretty uniform 110-120 ft lb from 2500 all the way to fuel cutoff at 8200 rpm. This is at the wheels.

Diesel

Same size diesel would be the Jetta 2.0 TDI. The dyno below is a stock 2009 VW 2.0 TDI. dotted line is torque.

This diesel makes much more peak torque (over 210 at the wheels vs 120) but less HP (~135 vs ~160 at wheels). The biggest difference is that it has really usable torque right off idle, whereas the gas engine is weak under 2500 rpm.

In this comparison in fact the Diesel has the peakier torque curve but since its peak is so low and the absolute torque is higher it would be easier to live with & drive and feel more powerful (nearly twice as powerful) to the typical driver who short shifts under 3000rpm. If you are willing to drive it like a race car (shifting to stay between 5000-7500) the gas engined RSX is a much faster car.

In reality what you are feeling as a "flatter torque curve" in the diesel is really a flatter horsepower delivery. The gas engine has a peakier horsepower delivery and thus has to be driven harder to feel powerful.

Well said!

 

[jharkin]

Well Im going to stand corrected on Diesel hybrids- look like at least one is out there, at least in Europe.

(broken link removed to http://www.peugeot.com/en/products-services/cars/peugeot-3008-hybrid4)


It will be interesting to see if we do get more diesel options here now that we have the ULSD fuel to make the clean ones viable (I think?). There is something to be said for just stepping on the pedal and getting power right now without having to downshift...

 

[Holzstapel]

I switched over to an 05 VW Jetta TDI 2 years ago from an 06 Jeep Rubicon. I have never been happier. I average about 43 mpg with my commute and I've gone 713 miles on a single tank. I love this car. It's fun to drive, has plenty of pick-up and the suspension i installed a few months back is outstanding on the curvy roads. I was paying over $500 a month in gas alone for the Jeep just to get me to and from work. I look back and laugh at how much a waste that was. I found a mechanic about 45 minutes away that specializes in TDIs and I have never felt so good about giving a mechanic my money. Great prices and very knowledgeable.

When my fuel light came on during the power outages from Sandy, I drove 25+ miles out to the nearest truck stop. Drive right past the line of gassers and pulled up next to the big boys and filled right up!

 

[velvetfoot]

Good web site for TDI: www.tdiclub.com

 

[Holzstapel]

Good web site for TDI: www.tdiclub.com [/quote]

Been a member since the day I bought her.

 

[343amc]

I was thinking of waiting for the Cruze diesel to come out back in March when I was looking for something new, but I got a heck of a deal on a 2013 Cruze Eco with 6 speed manual. The diesel version was going to be about $5K more. Plus I wanted a manual.

The image is from a trip back home from Gaylord, MI the other day. 51.5 MPG average over 158 miles. It's EPA rated at 42 mpg highway.

Sorry for deviating from the diesel topic, but the Cruze gas engines are definitely capable of 50 MPG if you drive conservatively.

 

[begreen]

Drove it again, this time with the windows open. Nice looking car, but the diesel is really noisy going uphill and we have a lot of hills. No comparison to the gas Cruze as far as noise goes.

 

[n3pro]

Drove it again, this time with the windows open. Nice looking car, but the diesel is really noisy going uphill and we have a lot of hills. No comparison to the gas Cruze as far as noise goes.

Thanks for sharing your experience. I've seen them advertised.

I'm surprised given as you and others stated how much quieter the newer diesels tend to be. I've considered a diesel work truck many times but as someone else said they typically only have then in premium package i just can bare myself to pay 40.000 + for a truck that is going to get abused. I typically get the bare bones versions.

I am not too fond on the pollution stuff. Had a rental straight truck for a week since somehow my truck was invisible at the loading dock. Anyway it was a 2011 International and every other day the particulate filter light would blink so I had to go through the particulate filter cleaning routine which was basically from driver perspective pull over in a parking lot, engage parking brake press the filter clean switch and check your email and social networks while the thing just revved up for 5 - 10 minutes. Seemed like I wasted more fuel and created more pollution then without the filter.

Looking forward to more diesel car choices. Diesels came a long way.

 

[begreen]

I was totally surprised too. You can barely tell a new VW TDI is a diesel. It's a pretty smooth and quiet car. The Cruze clatters like an old Chevette.

 

[begreen]

I had wondered the same, especially since this is a proven combination giong back 50 years or more in locomotives.

From what I read, there are a couple reasons its not done:

#1 - cost
Diesels are already more expensive to build than gas engines, and so is a hybrid. Put the two together and the cost premium wouldn't sell.

#2 - Combined efficiency
Gasoline engines are least efficient under low rpm / low throttle operation due to pumping losses. So in a hybrid you let the electric do most of the work around town (when gas is least efficient), and use the gas engine mostly at high speed where its operating at medium-wide open throttle under load and most efficient.

The diesel with no throttle losses doesn't loose as much efficiency at low speed and thus doesn't benefit as much from electric assist (other than the regenerative braking).

Volvo has a plugin diesel hybrid:
http://gas2.org/2013/03/13/diesel-plug-in-hybrid-volvo-wagon-coming-to-america/