The best mileage I had were temperature around 15 to 20 degree C (in Canada).
I had few more than 1090km per tank, trip from Toronto to Boston.
My average so far is around 5.9L/km to 6.1L/km. My family is very happy with it. I am thinking RX400h now...

 

I think my car does best for mileage any time the low temperatures are higher than 50 degrees farenheight and the high temperature doesn't cause me to use my AC too much. I've gotten 44.7 mpg before under those conditions, but lately I'm warming the engine each morning with my block heater. Hopefully I'll have space in the garage this winter so the whole car can stay warm. If the oil and batteries stay warm I'm sure that will help keep the mileage up a little. Unfortunately I think the oxygenated gas they are going to start selling here in the next week (winter) will drop my mpg's.

Someone asked how we get that many miles, I'm driving the back roads to work (the shortest route for me) and coasting as much as possible into the stop signs/lights. I also go a couple miles on just batteries when I come home. This tank I went way past the "0 miles to empty". I'm not sure how many, but I know my gas light came on at 582 miles (and I got to 714). It's not like I babied the whole tank though, I raced my brother's new Chevy Cobalt at a stop light. After initially falling behind I was flying by him around 35-40 (50 MPH zone).

I figured we could still get crud in our gas tanks over time, just from what might go in when they transfer gas into the stations gas tank. It's not like they keep everything really clean, and there is a lot of construction and dust around here lately. I've also seen bugs and all sort of stuff in the bottom of new "clean" oil barrels at work. I work in an aluminum mill and it's becoming common practice for us to polish (clean) the hydraulic oil before it goes into any of our systems.

 

Okay folks...I'm set to join the 700 club. I currently have 680 miles and just under the 1/4 tank left mark. The yellow fill light came on at 650 miles. The question I have is at 48.5 mpg can I reach 800 or will I fall short? I believe I have something like 32 miles to empty crusing range. Your help is apreciated.

 

I always assume that I have 16.2 gallons of gas available. I do the math for my FE and then calculate my expected range. Keep in mind that the indicated FE is normally high. I typically get 1 mpg lower than what is indicated. Based on this information, I don't think that you will get 800 miles. You need to be closer to 50 mpg.

 

Thing is--you _might_ be able to make 800, but is it worth being wrong? Maybe better off just sticking with say 750 miles this time, until you can build up a base of experience and data showing how much more fuel you had left for various distance/FE tanks. If you can reliably show that when you have 48.5 mpg and go 750 miles, you still have over a gallon left in your tank, it may be safe to push for 800. But I'd rather be safe at 700 (or now it's cooling down, 600 even) than start pushing it and find out I went too far...

 

Thanks all. Satisfied with 700+ so I will fill up on Tuesday. Will take a snapshot tomorrow and post final results.

 

I filled up after making an evening run to the cell phone store. So here are my results:

719 miles on single tank of gas
Average 48.5 mpg
Filled up with 15.305 gallons this evening
Price per gallon at Shell was $2.749
Yellow Fill Light came on at 650 miles
Mileage at Fillup: 19,588

 

The only time I feel comfortable going over 800 miles on a tank is when the MFD is better than 50mpg. I usually have a gallon or so left in the tank when I fillup. Been lucky so far.

 

Bugs,

Could you update your profile with the area where you live?

I'm guessing you are in a warmer coastal area. It's gotten too cold in the "North" for 47 MPG averages!

What kind of driving did you do for the tank?

I did a 47.6 MPG best tank, and a couple of 700 mile tanks - last spring when things started warming up. I was well on my way to a 50 MPG tank, but a cold snap hit for a week and destroyed it...

 

I live in coastal Louisiana and the 700 mile plus run was with mid to upper 80s and lows in the low to mid 60s on flat terrain. I lost the 800 mile run when we had a week and a half of colder temperatures in the low to mid 50s and highs in the mid to upper 60s. Brisk northerly winds I believe killed my chance of 800 miles as well as the temperature because I had 49.5 mpg before the cool spell came.

I drove in three school zones, two work areas (now paved very smooth) , and a stretch of city driving that allowed me to keep gliding along around 25 to 40 miles per hour. About 5 miles I would contribute to this type of driving. The other 25 miles was between 50 to 60 miles per hour. The 30 miles run was one way to work. Stopping to drop off the kids everyday. So I travel about 60 miles per day.

My gas tank ranges from 560 to 719. Most are around 600 miles. This latest 719 mile tank was under almost ideal conditions (with the exception of about a week and a half of cold weather). I don't expect to make 700 or even 800 until it warms back up.