NoahWeb

39.89 MPG w/ ACC set to 80-85, with a full trunk and back seat, driving between El Paso and San Antonio yesterday. The projected total range at arrival was 785 miles on a single tank!

.05/mile achieved!

#TDIwinning

KevinGary

It is amazing how well the TDI does on fuel.

2014a6tdi

That's amazing, considering you were at 80-85mph. Must have been a good tailwind!

I don't think mine would do that well at speed. Around 75mph I'm getting 39mpg. If I go to work at 70, I'll get there with 42mpg.

Rjim

I averaged 42 to 46 mpg (computer) on a five day road trip last June with the CC set at 78-80 mph, Minneapolis to Delaware to New York and back. Winter time is a different story. Minneapolis to Chicago and back at 15 deg. F, same speed, 35 to 37 mpg. Diesels like it hot, maybe more so than gasoline engines.

NoahWeb

Agreed on this...but maybe not hot. The temps on my drive were in the mid-60's and down to the low-50's by the time we arrived.

I have noted a huge drop off in cold weather though...estimate about 5-10 MPG in below freezing weather. Takes a LOT longer to warm the engine and drive-train up to normal.

tenspeed

That's why some trucks have the radiator partially covered in the winter.

http://www.ebay.com/itm/Fia-Big-Truck-Winter-Front-Grill-Radiator-Cover-Bug-Screen-BT1012-2-C-Series-C60-/121518369727?pt=Motors_Car_Truck_Parts_Accessories&hash=item1c4b0f2bbf&vxp=mtr

gk1

Much better than the 21 mpg I can manage in my S6 on a 180 mile trip at 8 degree weather. But I don't have the discipline to hold ACC the whole way so there are a few toll plaza romps and the last 15 miles are in dynamic manual mode. I will be interested to see what happens when the weather warms and we switch back to summer blend gas here in the northeast.

KevinGary

I live in the NYC area, where we are experiencing the third coldest February in NYC history. I noticed the mpg drop in my city driving. But I started adding opti-lube xpd at fill up about 3 weeks ago, and it seems as though I have returned to my summer mpg. Three weeks does not make it "scientific" but it seems promising.

2014a6tdi

Now, I'm in Coastal California so perhaps take what I say with a grain of salt, but, with my old gas car I got my best mileage during the winter and there was a 5-10% drop off in the summer. I'd guess it due to ethanol or something added to summer blend.

With my tdi diesel I'm seeing the exact opposite where during the winter I'm getting 5-10% worse mileage than I did during the summer and here in CA we don't have winter/summer diesel blends because it just doesn't get that cold.

I realize there are heaters for the adblue, the diesel lines, the aux heater for cabin heat, etc. Perhaps that's what is holding the stats down in winter.

Even so, I've never seen the computer on a trip say more than 43 mpg which is absolutely murdering the EPA estimates for this car, so I'm quite happy. My combined is 37 mpg over the "long term" which is the EPA highway estimate.

This car replaced a Lexus GS 460 (premium gas only). Just did my taxes and can absolutely say with this car my fuel bill is basically 50% less and I really don't see a massive step down in performance.

Rjim

Yes, it's probably more accurate to say diesels don't like it cold. I've been reading up on diesel fuel winter blends and the mileage drop off is definitely related to the fact that ULSD #2 is blended with ULSD #1 or other additives so it doesn't gel up as the temperatures drop. And Ultra Low Sulfur Diesel #1 doesn't have the same heat energy per gallon wallop as #2.