X5 4.8i mileage
 

My onboard computer says that I'm averaging 11.3 mpg. I do a mix of city and highway driving (in Houston). This seems on the low side to me. My driving style isn't aggressive.

Any suggestions on how I can improve my fuel economy? Has anyone installed a K&N air filter? Any other suggestions?

Thanks,

Steve

Reset your trip odometer the next time you fill up your tank and compute your MPG manually to start. Other than retuning your EFI for better mpg, I don't think there is much to do besides making sure your car is up to spec.

what's the total mileage on it? I saw my mpg (on a 3.0) get better after 5k miles for sure.

Get a 35d

It has just under 10K miles on it. I'll compute my mpg manually. What's the capacity of the gas tank? Does the onboard computer tend to be off? What type of mpg figures are people getting on their 4.8's?

Thanks.

I get 13.4 mpg on my 2008 4.8i. My commute is city and rush hour highway. Lots of stop and go. I'm heavy on the pedal.

The OBC is usually pretty close to actual mpg. I think the tank holds 22 gallons.

Correction - 22.5 gallons. Google is my friend. :D

Has anyone used a K&N air filter on their 4.8i?

I read somewhere that K&N filters really aren't that good for cars. Supposedly they really don't do that great of a job filtering dirty things from getting in (thus the increased air flow). Plus you really need to include cpu remap and larger exhaust to really take advantage of it. Not properly maintaining a K&N is bad too. I used K&N in my 3 series. Really didn't observe any noticeable advantages in MPG and power. Just gonna stick with the stock paper air filters and change them more often (if anything). I'm no expert, this is just stuff I read about from numerous sources somewhere.

My gas mileage got slightly better after 5000 miles. It averaged about 13.5-14.5 with a lot of traffic driving (it moves, but is slow and occasional stops).

But lately due to my change in route, it's gotten worse. I'm in the low 12's now. I've concluded that the main culprit to bad mileage is sitting at traffic lights where the vehicle just keeps consuming gas and does not move. My new route hardly has any traffic (so I'm cruising when I'm not at lights). Driving aggressively and moderately doesn't seem to have as big as an impact as being completely stopped. Wish I had Active Hybrid (like in the new 7 and the X6).

Its a 5 litre engine ;) no K & N paperwork will help that .. why did you buy it if you wanted economy ? :rolleyes:

That's why I waited two years for the diesel option. My diesel gets around 20 MPG city and 25 MPG on the highway...

Craig