So I recently took a trip to Tahoe to put some miles on my new TC (I must be the only guy eager to rack up miles... everyone looks at me like I am an idiot) and averaged 39mpg for the majority of the trip...

So here's the details:

Trip was from Santa Rosa to Kings Beach and back.

I intentionally took the steep route up 50 and all the way (to load up the engine) and drove around the lake when I got there at city speeds.

For about half the trip I had the windows up and the ac off. The other half either the windows were open or the AC was on.

The trip is a lot of uphill going and a lot of downhill coming back. I throttled it somewhat agressively up a lot of the hills but nothing outrageous and costed in neutral down most of them. I also dropped into 4th a lot on the long freeway stretches to keep changing up the rpms a bit as I am still under 1000 miles on my car.

I would think the uphill would have eaten enough gas to more than make up for the downhill sections on the way back but apparently not...

As I was running down to 1/8 tank I filled up and it came to 11.6 gallons (which makes sense if you figure 1/8 tank left is almost 2 gallons plus one more gallon for the empty light to run on).

Miles at the time of fill: 430.

So by my calculations that is 37mpg and change...

Now yes a lot of it was freeway, but a lot of it was uphill, a lot of the downhill was twisty and required braking thus loosing a lot of my free momentum and abut 60 miles of it was twisty country highway which wasn't near the same as normal freeway.

Maybe this isn't abnormal at all but it seems awful high to me.

The only thing I can think of that accounts for this is that I tailed semi trucks for a good 250 miles of the trip... I didn't tailgate them, I stayed a full 2 seconds back (to avoid rock chips and what not). I did it to avoid speeding as I was trying not to run the engine too fast during my first 1000 miles. Being behind trucks capped my speed between 55 and 65 for much of the freeway driving and MAY (even at 2 seconds back) have had some drafting benefit for the fuel efficiency.

Oh and don't go to Tahoe right now... bugs like crazy up there. 1 hour of driving and my bumper was COVERED in huge bugs. Hate to see what my radiator looks like right now.

 

I went to LA last weekend and got 32+ mpg on I-5 with AC on all the time. I usually get 23mpg with 40% city 60% highway

 

amazing MPGs!!!

 

the most i got was 34.6 coming from wichita ks to Huntington, wv

 

I've never ran a full tank out on just highway miles, so I can only figure my average for the tank, which never exceeded 25 in the Scion, and never exceeds 27 in the Audi unfortunately.

 

the max i have gotten here in miami is 20.4 MPG which i think is terrible

 

Interesting... 34.6 is not far from 37 so maybe it's not so impossible with really good conditions.

BTW I have only gone through 2 tanks on my TC so I am still early on in the game of calculating mileage.

 

That's about what I got when I went down.

 

If you think 20 MPG for the city is terrible, I guess you shouldn't have gotten a tC, since that is the rated mileage. Although you should be able to get higher than that if you keep your tires inflated and drive conservatively.

 

This is probably the MAIN reason you saw such high MPGs. there was a recent episode of myth busters (i believe) that tested it. they used a Dodge Magnum, first traveling alone at 55mph, scangauge read 32ish. then i think they started at 100 ft. behind a semi, up to 35ish (10% increase). then closed into 50ft, mpgs shot up to 38ish....

so you dont even need to be THAT close. wind resistance is a huge factor in your mpgs, which is why going slower is so much more fuel efficient.

i've been trying to keep it under 60mph lately, and have gotten over 30mpgs consistently on my last 4 tanks. i'd say 70/30 highway/city. and on long road trips i have seen upwards of 35mpgs (without tailing a semi).

 

i was also suprised at my gas mileage over the weekend. i drove to baltimore, md. A 140 mile trip and when i got there i had only used a 1/4 of a tank from full. This is with a turbo. Although I did cheat and set my vacuum AFR's to 15.0 at cruising on my F/IC

 

yea i drive like i need to be where i need to be... so just this sunday i went from ft. lauderdale to tallahassee. its about 475 mi. i filled up before i left and at half tank i had driven 160 miles... that means... my highway mpg is about 22... about 320 miles for a ful tank. and thats highway... wow

 

yea i drive like i need to be where i need to be... so just this sunday i went from ft. lauderdale to tallahassee. its about 475 mi. i filled up before i left and at half tank i had driven 160 miles... that means... my highway mpg is about 22... about 320 miles for a ful tank. and thats highway... wow

 

yea i drive like i need to be where i need to be... so just this sunday i went from ft. lauderdale to tallahassee. its about 475 mi. i filled up before i left and at half tank i had driven 160 miles... that means... my highway mpg is about 22... about 320 miles for a ful tank. and thats highway... wow

 

That's what I used to get going up... But now with my S/C...