Actual 80mph Interstate MPG

[jdpm]

I'm serioulsy considering a 2010 Jetta DSG for my 90 mile round-trip commute to work 5 days a week. I'm obvisouly interested in the TDI for it's mileage. However, I'd really like to know how badly the mpg suffers at 80mph.
I'd like to hear from others who consistanly drive their TDI DSG Jettas under the conditions. I live in FL, so basicly the highway is flat and the a/c will be usesed 7-8 months a year.
Please include your mpg conditoins such as speed, distance, terrain, and whether or not a/c is in use. I'd really like to hear from people who have hand caluculated their mpg.
If the tdi does not get a certain level of mpg for me, it will not pay to purchse it despite it's other positive attributes. Thanks in advance for everyones help. John

[Mrryan]

If it doesn't get the mpg you want at 80 mpg, what else were you looking at? Jetta are great highway cruisers because they were built for the autobahn and I don't know what else can get that kind of highway mpg outside of a honda insight or prius.

[thrab]

Friend has a Jettasportwagen with manual, not DSG. At 80mph it really doesn't make much of a difference though. You'll always get over 40mph even driving aggressively. Loading it up with bikes on the top or trailering is about the only thing you can do to really kill it.

[Stewart]

most likely mid to high 30's. My '10 jsw on a calm day at 75 will just push 40mpg with any wind its going to be around 37 to 38 mpg. At 65mph it climbs to 45mpg. Faster you go the worse its going to get.

[jdpm]

I appreciate the feedback. I had a 2006 Honda Civic with 5 speed auto that consistanly got 34-35 mpg at 80mph with the a/c here in FL on I-95 on my weekday work commute.
I also have a 2010 auto rated at 31mpg, however, under the conditions I drive, it is only getting 25-26.
I have always liked the VW's and almost bought one last year. But the numbers just didn't work out. Wih the price of diesel running 30 cents higher than gas and the higher cost of the TDI, it would not pay to buy a TDI if it did not get the mpg of my previous Honda.
This is not intended to turn into a debate about Honda vs VW, just simply a mpg question.
Again, I appreciate the real world mpg of those who drive like I describe. Thanks. John

[thrab]

Having the A/C on is not going to hurt your mileage at all. Having the windows down will definitely hurt it though! Honda makes some good gas engines, very nice fuel economy and just enough power. Still, prefer the TDI to get ridiculous torque for the mileage.

[ksing44]

My global average is just over 40mpg in my 2010 Golf TDI 4-door manual. I drive 80 miles per day, mostly on the Pennsylvania turnpike at 75 to 80mph. I typically average about 45mpg on the way to work and 42mpg on the way home, but then I lose a little mpg driving here and there around home. If I drive 65mph, I can get 50+ on the way to work and 45+ on the way home. So generally, I think you take about a 5mpg hit going 80mph instead on 65. *Note: The terrain here in southeast PA is a little hilly.

The Prius is better, a number of my friends get 50mpg or maybe even more if they are careful. They also get to use regular fuel, which costs significantly less than diesel in my area. In my area, diesel costs as much or more than premium. My car is significantly more fun to drive, however, and mostly my friends seem to like my car more. I know I don't want the Prius, but it does get great mpg.

Honestly, considering the cost of diesel in my area, some other cars would be as cost effective or even more cost effective. For example, a regular old Honda Civic gets in the low to maybe mid 30s for mpg on the highway. They also use regular gas, so the reality is the Civic might cost about the same for fuel. I think it also costs much less to purchase a regular Civic. With the hybrid Civic, it would likely get the same mpg as my TDI, but you would save buying regular gas. The Prius is the clear winner for cost of fuel.

I love my TDI and would not switch, but there are some costs and also the odd-ball things about owning a diesel. That is the reality.

[philcollison]

Expect 40 mpg with a steady 80 mph on a flat highway. I set the speedo at 74 on my 100 mi commute and get 42 on average. 40 of 100 miles is on secondary roads at 60-65 so a bit better, but you can expect 40 mpg.

[suparag]

Hi,

I have a 2006 Jetta TDI w DSG Transmission, and I drive about 96 miles to and from work, and twice a month 320 miles in the weekends. I keep meticulous records of my mileage since I bought the car, and most of my commute is highway 80% highway and 20% local.

Here is what you can reasonably expect mileage wise.

At speeds of 75 - 80, with or without ac you will get about 38 or 39 mpg, which I used to get. In Jan 2009, I resolved to drive at speed limit, so I started driving at 70 mph on highways, my mileage increased to 42 - 43 mpg. Keeping the tire pressure high (40 - 42 psi) helps increase your mileage slightly, but you compromise with slightly higher road noise and harsher ride.

Right now I have 149k miles.

[jdpm]

Thanks for the replies everyone. This is making the Jetta look even more promising for me - especially since I have just seen an ad today for $4k off all remaining Jettas in stock! john