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Audi banking on Gen 2 3.0L TDI diesel for US sales; calls for a “fair shot” for diesel (update w/ rally results)

Audi's Gen 2 3.0L TDI. Click to enlarge.

Audi of America introduced four new TDI clean diesel models for the US market this year—the Audi A8, A7, A6, Q5—along with an updated Q7 TDI, all equipped with a second-generation 3.0L V6 TDI diesel engine. (Earlier post.) This week in Washington, the company held a series of media drives (“TDI Efficiency Rally”) for the Q5, A6 and A7 diesel models to highlight their efficiency and performance, and also offered up its—as well as several other experts’—perspectives on the potential for diesel in the US market.

If we are going to reward efficiency, and that’s the goal,” said Joe Jacuzzi, Chief Communications Officer, Audi of America in opening remarks, “then diesel really needs a fair shot. Not only is it more powerful and contains up to 30% better efficiency than traditional gasoline, etc. The fact of the matter is [it requires] very little infrastructure change and secondly, its a very simple driving behavior change. You move from one pump to the other.

One of our primary goals and objectives is to level the playing field for clean diesel vehicles. Our challenge, well, President Obama in one policy statement after another has advocated for an all of the above strategy when it comes to sustainable mobility. And yet clean diesel, one of the cleanest choices for putting the US on the road to energy independence, hasn’t see any sort of incentive since the Energy Independence and Security Act (EISA) of 2007.

TDI clean diesel represents almost 25% of Audi and Volkswagen US sales. Are these sales incentivized? No. Do they receive HOV access for their improved fuel economy and ultra low emissions? No. Do they get state or federal tax breaks? No. In fact in 6 of the states, diesel fuel is penalized with additional state taxes. So diesel fuel gets taxed twice or penalized twice at the federal and state level. The only incentive that TDI vehicles receive—and it isn’t doled out by the US government—is almost consistently best-in-class fuel economy, reduced CO2 emissions and clean diesel drivers knowing that they are doing their part to reduce the impact on the environment.

—Anna Schneider, VP Industry and Government Relations, Volkswagen Group of America

(Schneider leads all advocacy efforts for the Group at the federal and state level. Previously she was vice president over government relations at Toyota Motor North America and executive director, government relations at Mitsubishi Motors North America.)

Market. During his presentation at the TDI Efficiency Rally, UMTRI researcher Bruce Belzowski first presented a summary of his analysis of the total cost of ownership of diesels with a comparison to that of their gas vehicle counterparts. Essentially, Belzowski and his colleague Paul Green found that drivers of diesel vehicles can save thousands of dollars in total ownership costs compared to similar gasoline vehicles. (Earlier post.)

In that study, they developed three- and five-year cost estimates of depreciation by modeling used-vehicle auction data and fuel costs by modeling government data. They then combined these estimates with three- and five-year estimates for repairs, maintenance, insurance, fees and taxes from an outside data source.

Belzowski also presented preliminary results from a survey of powertrain experts—from automotive manufacturers, suppliers, government, NGOs, academia and consulting—asking for their predictions of powertrain penetrations for 2016, 2020, and 2025. The survey is similar to surveys run by UMTRI on the same topic in 2006 and 2007. The results so far suggest that:

  • The penetration of spark-ignited engines in passenger cars is projected to drop to 51% in 2025 from 74% in 2016. At the same time “advanced diesel—which doesn’t have a specific technology definition, Belzowski said, but instead is whatever a given expert considers will constitute “advanced diesel”—will increase to 12% in 2025 from 8% in 2016.

    For passenger cars, hybrids will continue to claim a larger share of the market than diesel, rising to 28% in 2025 from 15% in 2016. Fuel cells are seen as hitting 1% by 2025; extended range electric vehicles, 3%; and battery-electric vehicles, 4%.

  • The penetration of spark-ignited powertrains in light trucks is projected to drop to 55% in 2025 from 74% in 2016. Advanced diesel will increase to 23% in 2025 from 17% in 2016.

    The 2025 diesel share is higher than the projected share for hybrids (17%); both hybrids and diesels are far beyond the share of the other types of powerplant listed (HCCI, fuel cell, extended range electric vehicle, and electric): 1% apiece.

A separate forecast from LMC Automotive, shared by Audi at the event, projects diesel volume in the US growing from 445,376 units and 3.2% marketshare in 2012 to 1.25 million units and 7.4% marketshare by 2018—i.e., share and volume are expected to more than double from 2013 to 2018.

LMC’s forecast suggests that pickup trucks will represent a shrinking percentage of total diesel sales in the US, dropping from 66% of diesel sales in 2012 to 35% in 2018. That drop, however,is offset by significant growth in sales into the SUV segment—an increase from 8% of total diesel sales in 2012 to 26% in 2018.

The company sees the percentage of diesel sales into the compact car segment growing from 4% in 2012 to 11% in 2018. Van share grows from 5% in 2012 to 12% in 2018; and the midsize car share of total diesel sales drops from 17% in 2013 to 10% in 2018.

Updated 3.0 TDI coming at Frankfurt
Audi is refreshing its flagship A8 luxury sedan with a number of technology updates, including more power and efficiency from the gasoline and diesel engine range.

Among the changes is a new 190 kW (258 hp) 3.0L TDI—a version of the second-generation version of the 3.0 TDI diesel engine featured in the diesel-fueled Q5, Q7, A6, A7 and A8 in the US market.
The refreshed A8 will be shown at the upcoming Frankfurt Motor Show.

The 3.0 TDI. Audi is only applying the new second-generation 3.0-liter TDI in the models currently on sale in the US: the Q5, Q7, A6, A7 and A8. The engines are paired with 8-speed Tiptronic transmissions.

The first generation 3.0L TDI delivered 225 hp (168 kW) and 406 lb-ft (550 N·m) of torque; the current second-generation engine is 55 lbs (25 kg) lighter (from 458 lbs to 425 lbs), and delivers 240 hp (179 kW) and 428 lb-ft (580 N·m) of torque. (The Gen 2 engine is also a bit shorter than its predecessor.)

The company had set a number of development objectives for Gen2 of the engine, said Axel Macher, head of Thermodynamics/Application V6 TDI at Audi in Neckarsulm, Germany. These included:

  • Higher power and torque;
  • Lower fuel consumption;
  • Meeting ULEV2 emissions;
  • A start-stop system;
  • Minimized weight;
  • Compact design;
  • Acoustic refinement;
  • Modular construction;
  • Optimized driving dynamics; and
  • Optimized production time.

Audi took 26 lbs (11.8 kg) out of the crankcase, crankshaft, main bearing frame and upper oil pan—the last by switching from aluminum to magnesium. Macher noted that Audi has a new machining process that allows them to make a cylinder bore that will be perfectly round when the engine is operating. “If you have a perfect round bore in engine operation mode, you can reduce the pretension of piston weight, and that reduces friction,” Macher said. Laser smoothing of the bores also reduces friction.

Further contributing to a reduction in friction was going from four chain drive chains to two, as well as a reduction in weight of 8.8 lbs (4 kg).

For the second-generation, Audi further optimized the turbo with integral insulation and by moving away from flange-based mounting to the exhaust manifolds to an integrated component. Reducing thermal mass, it enables the turbo to reach operating temperature more quickly in the heat up phase. Audi also specifically optimized the turbocharger for the North American market to deliver very quick performance off the line. (A design target that appears definitely to have been met, at least subjectively, based on our experience in the TDI vehicles.) In Germany, Macher noted, the turbo is optimized for longer stretches of high-speed autobahn driving.

Changes in the exhaust manifolds and turbo from Gen 1 to Gen 2. Click to enlarge.

Injection pressure in the Gen 2 3.0 TDI is raised to 2000 bar, helping increase the power output and reduce emissions. The piezo injectors also use a multi injection strategy—two small pilot injections, followed by the main injection, followed by a post-injection. This strategy contributes to the quietness of the engine.

You need high EGR rates so you can reduce 70-90 % of the NOxemissions. With the second generation of the diesels, we have a bigger EGR cooler, we have tubes with a bigger diameter, so we have less gas flow resistance. This helps us to make better fuel economy and good emissions.

—Alex Macher

Cooled EGR system. Click to enlarge.

Exhaust gas aftertreatment system, shown in an A7. Click to enlarge.

Driving the cars. For the rally, journalists paired up first to drive the Q5 TDI, then the A7 TDI, then the A6 TDI. All cars followed the same courses for each vehicle set, and the objective was to come back with the lowest fuel consumption.

The TDI Efficiency Rally fleet. Click to enlarge.

The course was primarily in the Virginia countryside—not a challenging terrain, but with rolling hills, some winding curves, and a few small towns. Exposure to Washington DC beltway-type traffic jams was minimal, and city driving was also minimal.

In other roads, the route was selected to showcase one of diesel’s strengths—efficiently cruising down the highway.

Audi collected fuel economy data from each car for each team at the vehicle changeover, then collated and analyzed it all at the end of each day for four different waves. (The last wave is concluding today, Friday.)

EPA estimated fuel economy (mpg) for US TDI models
Model City Highway Comb.
A6* 24 38 29
A7* 24 38 29
A8 24 36 28
Q5* 24 31 27
Q5 hybrid** 24 30 26
Q7 19 28 22
* denotes a model in the Rally
**for comparison

Subjectively, while each of the three models has its own special attributes, whether in terms of appearance, road hugging, handling, etc., uniformly the diesel powerplants proved exceptionally quiet, responsive, quick and powerful.

Assisted by selecting “Dynamic” driving mode, the diesel on more than occasion could shove us back in our seats—during a quick acceleration maneuver to make a left turn onto a highway with relatively high speed oncoming traffic, for example. There was no discernible lag on kickdown.

While outside the vehicle, they are audibly diesels (but not obtrusively so), inside the cabin it’s difficult to tell. Audi did a superb job of acoustic management with this generation of its US diesels—much more so than on the earlier 2009 A3 TDI, which, for all its pluses, had a distinctive diesel sound. (When that model was in the sales mix, Audi said, it also accounted for 55% of A3s sold.) Under the range of speed and traffic conditions on the rally, the inside of car was extremely quiet.

The stop-start function works flawlessly, without any untoward shaking or rumbling as it shuts the engine down or restarts.

And definitely one of the pleasures of cruising around the countryside in comfort and quiet was glancing at the fuel indicator and seeing how much was left.

Ideally, Audi team members suggested, the TDIs wouldn’t necessarily be targeted to diesel enthusiasts per se, but rather to buyers who simply want that combination of performance (not necessarily upper-end sport-class performance), low emissions and fuel economy—especially on the highway.

And, back on the policy front, Audi would also like Jacuzzi’s “fair shot”.

One of the challenges I see [facing diesel] is the way EPA weights city and highway driving when it comes to the label values for fuel economy. Currently, city is weighted at 55% whereas highway is at 45%—which obviously is going to favor your hybrids. I would argue that that’s not typical of the average person’s driving. In fact, the numbers I have seen are that people do 55% highway driving and 45% city driving. So right away we are penalized when in fact I think the fuel economy numbers would be much higher if they reflected real world driving.

As we know, and as you all are experiencing in your test drives, our label values... we exceed them consistently. You go to, and you’ll see that time and again people are experiencing much higher fuel economy than the Monroney label [the required window sticker on new cars].

—Anna Schneider

(GCC will post results from the TDI Efficiency Rally when Audi has collected all the data. Audi hosted GCC at the TDI Efficiency Rally.)

Update: Fuel economy results from Wave 2 of TDI Efficiency Rally.

A6 TDI results. Click to enlarge.

A7 results
A7 TDI results. Click to enlarge.

Q5 TDI results. Click to enlarge.



Audi should not expect a "fair" treatment if they introduce diesel cars in the USA. It might not be suicide but perhaps like shooting yourself in the foot. It is not an easy task to gain acceptance for diesel cars in the USA. Just the fact that they have 30% better efficiency is not a sales argument that people even bother to consider. Perhaps people would get interested if they claimed that the cars use 30% more fuel.


Since I suggested a Diesel Genset over ten years ago no big automaker has put any time or money into producing an experimental design. I am convinced the state of the art in automotive design would require Diesel as the primary power source for the next 60 to 75 years.

When other power sources, including some that have not been thought of yet, are developed to the point where they out perform Diesel, then it will become obsolete. Never forget that Hydrogen and all types of batteries are not power sources.


Can't condemn Audi/Volkswagen for wanting to expand their niche in the American market. But beware of the Diesel/Petrol ownership cost comparisons suggested here. The choice is between the mundane to awful petrol mpg performances typical (until quite recently) of German cars sold in the US and their not surprisingly high-achieving diesel counterparts.


Love the EGR and the start/stop...but KILL V6s...4 cylinder diesels, even with twin sequential turbos, or if you dare, electric rear-drive are ALL thats needed.

Thomas Pedersen


You are so right! The current strongest two-litre diesels have plenty of power for high-speed cruising. All they need is perhaps a 100 Nm e-motor for that last oomph to kick you back in the seat during accelerations. The e-motor will also reduce the peak strains on the engine giving longer lifetime (I suppose).

Include improved kinetic energy recovery and you have instantly taken a step change in fuel economy. And as you say, a rear-wheel driving motor negates the need for complex mechanical integration, although many manufacturers have all but solved this issue.

Really, I think many manufacturers are implementing mild hybrid and hybrid tech 'as slowly as they can get away with'. By adding features already developed over a longer period of time allows more income as extra charges for new/extra features.


Don't forget the reasons why Americans have such a negative bias about Diesels.

The entire GM executive staff deserved to be put on trial for what they knowingly did. If you don't know what I'm talking about look at this and do your homework.


I am old enough to remember this, although I was not aware of this site. However, most people involved in this scandal are either retired or dead today. I do not think average Joe in the USA knows very much about this or even consider it when he goes to the car dealer. It really has nothing to do with Audi either. In addition, I do not believe in the concept of original sin. The reasons for low acceptance of diesel cars should mainly be looked for elsewhere. In Sweden the public did not like diesel cars either. Sales were less than 10% a little more than a decade ago. Today it is well over 60%. Eventually, dealers found out a decade ago that if they just could persuade the customer to have a test drive, the car was more or less sold. Recall that in those days, most gasoline cars had naturally aspirated engines with low torque and at high engine speed. Getting the experience to drive a car with the superior torque and corresponding drivability of a turbocharged diesel car convinced most potential buyers. Better fuel economy was a surplus benefit. Perhaps Audi could learn from this experience for their marketing in the USA.

Thomas Pedersen

Peter XX,

The reason why your strategy main be less effective in the US than in Sweden could be that American cars are generally equipped with much stronger engines that do not required high rpm to achieve moderate acceleration. Also, 2000 rpm @ 60 mph is not uncommon.

Anyway, they should give it a try. The strong pull from a diesel is very comfortable - and addictive. Last time I drove a small petrol car, I almost thought they had forgotten to put the engine in...


I suppose you imply that lower is better, i.e. downspeeding. I get ~1750 r/min @ 65 mph in 6th gear with my 1.6-liter diesel engine. If a larger gasoline engine in the USA is the reference, I suppose a 6-cylinder diesel engine is what we should compare to. As low as 1500 r/min @ 60 mph is what we could expect for the diesel option in this case. With twin turbo, even lower speed could be possible. We also need some boost pressure at low speed. However, to get down to 1000 r/min an “active” pendulum flywheel damping would probably be necessary for NVH reasons. The latest BMW 320d Efficient Edition has that and it is said to be comfortable at 1000 r/min but I have not tested this car. In my mind, downsizing is also important but that is another topic.


The USA already has created and given each automotive technology an "even and fair" shot. The standards neither reward nor penalize any heat engines. All must meet T2B5,( Clean Air) emissions standards. Period.

These regulations will soon be tightened to T2B2, (Pristene Clean Air), or in CARB speak, SULEV II. Which about 25% of California's vehicles already meet. This level of emission is what the EVs produce, and is considered a Zero Emission Vehicle.

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