Wow! I reached 23mpg...
 

Wow I cant believe it, but yesterday going to see my kids in Ontario California from Los Angeles California I reached 23 mpg... I believe if I continued on the 60 freeway I could have reached 24 mpg?

Wow I was in shock... is this believable? someone posted they reached 23.5 and I was a little bit skeptical, told me to put in Chevron Techron fuel injector cleaner bottle (big size), and fill up with Shell 91 premium! and wow!.. im shocked..

Calculated, or based on the computer? I find the average fuel economy calculated by the computer to be 1 mpg high. Our 1999 328i was 2 mpg high, every time. That being said, after the exhaust work, I can get 24 mpg highway. I haven't done a decent trip after I put the CAI on to see if it helped any.

I'm actually shocked at how low some are getting with the 3.0. Even when I drive mine pretty hard I still get 17 in town. My wife gets 19 with her driving style. Of course "city" varies depending on where you live. What do you get in town?

Yep, I've reached 23.5 mpg before. However, soon after that my MAF died. I think the resistor had been gradually changing and it was perhaps giving me a slightly lean condition without setting off a code. Once I changed the MAF, I had the experience of enormous power :) and my mpg went back down.

How slow were you driving?

I was going 75 mph straight on the 60 freeway from Los Angeles to Ontario, right before the 15 freeway. Its a stretch of about 44 miles.

The funny thing is I wasnt even using Cruise Control, I just resetted my computer to see what my MPGs where gonna be, i slowed down to 60 mph before I reached the Haven exit...

on the way back I reached 21 mpg. Im shocked though It was a beautiful day here in Southern California, 82 degrees, it was a beautiful drive to Ontario.

I was gonna take my Metro 3 banger because of the drivem, but I decided to take the X with the panaromic sunroof.... BY the way had both front windows down, my moonroof open enjoying the music and wind, cruising... LOL, when I looked at the computer I was like WTF? wow.... Really happy!

P.S. my city is terrible its 15.5, 16.00 mpg

I just completed a trip on I-65 and I was able to get 23.7 calculated using 93 octane 100% gasoline that I found in TN. Unfortunately, I couldn't find another 100% gas station the rest of the trip. Congrats on your excellent mileage!

wow.. that is amazing...

1. Is this only available only on the 3.0 six?
2. Or are our friends with 4.4 and 4.8 getting the same results?

Re: Wow! I reached 23mpg...
 

It is pretty cool. On all freeway at 70 I can maintain 25.5 on the computer. I would be thrilled though if my MAF was bad. I'd rather have more power!

23 mpg on highway fully loaded
 

I've gotten 23mpg on longer trips with a fully loaded X5. By fully loaded I mean 4 adults with luggage. I didn't use the trip computer either. I calculated the mileage by dividing the miles by the gallons used. I checked it over long distances and full tanks. This was with the 3.0 of course. I also got over 20mpg with the 4.8 on my last long trip. The key to this is keeping the speed to around 70mph or less. I'd like to know what it would be if I kept it at 55, but you get run over at 55 mph on most highways. In fact, it's hard to kept either X5 under 80 unless you really concentrate or set the cruise control.

I never did a scientific test but I normally get about 12 MPG since not alot of highway driving.

However, I'm fairly confident that my X could not get that kind of mileage staying at 70 MPH on the highway! ;)