Is the 2010 Jetta TDI's MPG rating exaggerated?

I have a 2010 Jetta TDI with the 2.0L engine and the 6-speed DSG transmission. Previously, I had a 1999 Jetta TDI with the 1.9L engine with a 5-speed manual transmission. On a typical SFO - LAX drive (and back) the 1999 Jetta never got less than 42 MPG; I once drove it exactly 800 miles from Fauntleroy Way SW & SW Alaska St. in West SEA all the way to San Pablo & Knott Aves. in El Cerrito, CA, just off of I-80 at exit #15 - on one tank of fuel. While the fuel tank's capacity is given as 14.5 gal., it's noteworthy that the tank was topped off completely in SEA; the MPG was 45.7, what with having used 17.5 gallons over those 800 miles. (Yes, I also topped off the tank completely in El Cerrito.) This MPG figure was achieved with a cruising speed of 75 MPH - using the cruise control outside urban areas - and the usual brief bursts of higher speeds for overtaking & passing. Given the real-world driving conditions of that trip, the fuel economy was outstanding.
Now, my 2010 Jetta TDI simply never has exceeded, let alone achieved its 41 MPG rating on trips to SEA, LAX, or SAN (Diego), this while cruising at 75 MPH and only going faster to overtake & pass - that is to say real-world driving conditions. Is everyone else with this model getting better fuel mileage, or is there something wrong with my vehicle? Would selection of a manual transmission have given better fuel economy?
I hear conflicting opinions about whether the DSG transmission is more fuel-efficient than the six-speed manual transmission. I have a bad feeling that selecting the DSG might not have been the best choice for fuel economy. Routine maintenance of this type of gearbox is going to be more expensive because it needs to have its oil changed periodically. If I ever buy a new car, it'll be with a manual gearbox.
Oh, I had a 1982 Rabbit diesel (five-speed manual) prior to the 1999 Jetta TDI, and its highway MPG was 35 to 36 MPG, so the 1999 Jetta TDI was a major advancement in fuel economy AND performance that really flummoxed me. Alas, this doesn't appear to be the case with the 2010 TDI; I'm crestfallen instead. Now, before the hypermilers chime in, bear in mind that real-world driving conditions on long trips on interstate freeways DON'T entail plodding along at 50 to 60 MPH. The bottom line question: Is anyone out there with a DSG-equipped 2010 Jetta TDI getting 41 MPG or better under real-world long-distance freeway trips?

I don't think that it's exaggerated. I get 46-48MPG with complete highway driving at 74mph. then I get 38-42mpg with mixed driving. Reading from everyone else they are all getting about the same mileage.

What type of gearbox is your Jetta equipped with?

I have a 2010 with a 6M. With 4 people and a trunk full of luggage, I can get upper 40s for mpg on a highway, hilly, speed around 70 mph. Flatter routes have gotten me 50+ mpg. Mileage, though, can be negatively affected by a lot of factors.

Our worst tank so far with our DSG Sportwagen is 41mpg with a mixture of city and open driving. We currently have 48k miles and the car has been impeccably maintained. Tires at 90% of max psi being our only mpg mod along with my light foot.

This is our family car, driving with my girls in it most of the time leads to more cautious/slow driving. Extendo interstate driving returns upper 40's easily with the cruise and everyone on board.

The DSG has a shorter 6th gear than the 6MT so that does hinder MPG a bit. With my 6MT, cruising around 72-73 nets upper 40's, where as 75 or so is around 45 depending on how I drive. And try making the trip with just your right foot instead of cruise control. This allows you to plan ahead for hills, like building momentum going down hill and using it for the next incline.

Getting the largest average of the same engine type would be a more accurate MPG expectation. Fuelly reports for the Jetta sedan for 2010-14 diesel engine is as follows:

2010: 39.4 MPG
2011: 39.2 MPG
2012; 40.3 MPG
2013: 39.7 MPG
2014: 39.5 MPG

for a total of 536 TDI CR VWs with over 32 million miles reported. Do we see a consistency here?

EPA numbers for you '99.5 were 42/49. For your '10 they're 30-42 or thereabouts. If you edit the '99.5's numbers to the new EPA standards it would show 44 MPG highway, meaning you got slightly above that number one time. And your '10 is within 1 MPG of the current highway number. Sounds OK to me.

RDC98tdi: So, MT's give better mileage because they have a longer top gear? Interesting. I wonder why they put a shorter top gear in the DSG.

Natehack: What's your cruising speed for the extended interstate driving?

Hughesjasonk: What type of gearbox do you have?

Sounds OK to me. Under the same conditions, your 90hp '99 with a manual gearbox will always get better fuel economy than your 140hp '10 with an automatic. But your '10 is faster, cleaner, and roomier.

John SFO said:

RDC98tdi: So, MT's give better mileage because they have a longer top gear? Interesting. I wonder why they put a shorter top gear in the DSG.

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I have no idea why the DSG has a shorter top gear, maybe someone more knowledgeable can chime in. But I know that with a speedometer indicated 75 MPH (GPS ~73 mph), I am only turning 2000 RPM, which is right in the torque sweet spot. Dad has a '13 with DSG and I believe he is turning around 2400 at the same speed, correct me if I am wrong.

Soon the Jetta/Golf TDI's will be equipped with a urea injection system similar to the one the Passat NMS currently has. So we should expect their mileage to overtake the one of the Passat as it is expected based on the size/weight of each vehicle.

2011, dsg, 70K, wife averages 42mpg mixed tanks.
Around 48 @70mph
51/52 @55-60mph
A/C drops 2mpg

I hear the dpf affects the mileage big time.

JasonG said:

Around 48 @70mph
51/52 @55-60mph

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This is almost exactly what I'm seeing with my DSG Golf (calculated over numerous 600+ mile trips). I think the DSG penalty thing is a bit overblown.

Fuel economy seems fine to me.

On my road trip from TN to NJ, of about 680 miles, I got 43mpg on the trip up, driving mostly around 75mph, and fairly aggressively. Wasn't paying attention at all until the very end to calculate it. On the trip back I got 46mpg, driving around 65 (there are interstates and highways on the route that had 70mph limits, I went the speed limit there), not hypermiling, but I did pay more attention and adjusted my driving style.

John SFO said:

RDC98tdi: I wonder why they put a shorter top gear in the DSG.

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I have been asking that question for months, and nobody on this forum has given me an answer. It makes no sense to me. I just drove a rental Ford Escape last weekend. At 70mph it was revving at 2000, while Jetta TDI with a much torquier motor will rev at 2300. To be honest such a short gear is the biggest complain I have about the DSG. What a waste of low end torque!!!

The only possible reason I can think of is to get you into 6th gear at a lower speed - I know in suburban driving I'm cruising in 6th @ ~45 mph. Of course whether or not you think that was a good design strategy is certainly debatable, but I have no complaints with the results I'm getting.
It's a compromise, but it's optimized to exploit that low end torque while cruising at less than hwy speeds - which for most people is probably where they do the most driving. My mileage is probably 80% hwy, and my #2 memory avg consumption, which I never reset, always reads 50 something (minus 7% calculated error)
I like the fact that it effortlessly eats hills in 6th even as slow as ~50 mph without even thinking about downshifting (which of course is meaningless if you drive mostly flat terrain, but it makes me happy).

My lifetime average at about 70k miles is just over 40 mpg in the JSW with dsg. I've posted many times before that this is about 5 mpg lower than my 2000 tdi 5 speed beetle over 140k miles. 2010 weighs more, is bigger overall, has a larger engine with more power, and more emissions controls. It's also a nicer car that will probably be in my driveway for another 70k miles.

I wish I could get a lower gear in the DSG.. I spend a good amount of time at 75+ and it seems like the little CR is being over worked.

Right or wrong, from a layman, I think the gearing/shift pattern should be modified slightly.

Even at 75 mph, the diesel will be spinning at a lower rpm than the gasser. I haven't done a direct comparison in my newer cars, but on my old 2000 beetle, it got the best mileage around 58 mph. Up around 70, I started to see a drop in mpg. I'm sure others have done that comparison and it may show up in a search.

It certainly isn't being "overworked" by the slightly shorter 6th gear, and it allows you to use 6th more than you otherwise would, which increases your overall efficiency as long as you aren't doing consistent high speed driving. If you are, then what is the point of the auto anyway?

People worry too much about RPMs with TDIs. My older cars would all run happily at 3000 RPM for hours and deliver over 45 MPG doing it. Can't do that in the '12, because it would be going 'way too fast at 3000 RPM.

I believe all 6 gears are shorter in the dsg then the corresponding manual gear. I believe this is so as other pointed out you are in 6th quicker so overal city milage is better. Also they advertise the dsg as being quicker this equates to most people as being faster and since nobody is going to go the 150+ to max out either tranny this allows VW to advertise the dsg as a faster car as well. In america faster always sells and lower 0-60 times always equates to a higher demand/selling price than say a 12 second hybrid by another car maker.

Ron

I understand the "real" reason behind the shorter 6th gear in the DSG, but a lot of people that buy the TDI (no matter what the transmission), do more highway miles than city. Highway is where the TDI shines, and that's why the 6 speed manual shines more than the DSG. I understand if you do a ton of city driving, or you're like my dad who has slightly weaker knees due to age (doesn't want to manually shift all the time) that the DSG is logical. But for highway mileage, the 6MT (and a tune!) makes the CR one of the best combinations of power and economy you can get anywhere! Plus, I love rowing gears and love being in control. Even when my 16 mile commute takes 50-60 min because of stop and go traffic, I enjoy my clutch.

Hell, I drove 95 miles to and from Cincinnati with my boss the other day (he has a 2008 328i Bimmer), and he commented on how my car felt way faster to 70 than his. Granted, I paid $500+ for a tune, but in the long run I feel it was worth every penny!

This is for the 2012+ Passat. I'm not sure how the other models compare:



The DSG has a smaller gear spread than the 6-sp manual, 6.1 vs. 6.6. I suspect the DSG overall gearing is skewed for acceleration at lower speeds as well as the EPA highway drive cycle with spends a lot of time at light acceleration 40-60mph in which the DSG is happy in 6th gear.

APT said:

This is for the 2012+ Passat. I'm not sure how the other models compare:

The DSG has a smaller gear spread than the 6-sp manual, 6.1 vs. 6.6. I suspect the DSG overall gearing is skewed for acceleration at lower speeds as well as the EPA highway drive cycle with spends a lot of time at light acceleration 40-60mph in which the DSG is happy in 6th gear.

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Great post -- interesting data, and point about the highway EPA test cycle.

IndigoBlueWagon said:

EPA numbers for you '99.5 were 42/49. For your '10 they're 30-42 or thereabouts. If you edit the '99.5's numbers to the new EPA standards it would show 44 MPG highway, meaning you got slightly above that number one time. And your '10 is within 1 MPG of the current highway number. Sounds OK to me.

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There is a large difference between highway mileage,and city mileage with my 2010 JSW w/the 6 speed manual. I get about 41 on the highway. 30ish around town. Gotta say that I am disappointed verses the numbers that I used to get with my '99 Golf(45 MPG in combined driving) (up to 52 MPG on the open road.

The TDI shines in the city. On the highway, fuel consumption of gassers gets very close to the TDIs.

Max Period said:

The TDI shines in the city. On the highway, fuel consumption of gassers gets very close to the TDIs.

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I always thought it was the opposite. Hmm.