First Big Trip with the 50i
 

I went to Charleston, WV and back today, a 490 mile round trip. With some traffic and city driving, average speed was 70 mph and I got 19.6 mpg. I was hoping for better mileage but I did enjoy its power in the mountains so I'll take the blame for some loss of MPG. At 1700 RPMs in 8th gear it had no issues pulling the mountains but in D it would downshift to 7th on the longer ones and stay there. I enjoyed the toll stops and would leave the booth in DS letting it wind out a bit getting back to speed. I also used sport mode in the twisties and still had a good ride. Overall I really like the ride/handling balance with the 19s. It's a great vehicle for trips.

PS: 900 miles down, 300 to go and it's broken in. Then the MPG will really nose dive as I play with what it can really do!

Well, I am impressed.

I just finished a 10 day vacation with the X5 50i. 1770 miles, 18.5 MPG, probably 90% highway, 5% city, and 5% WV country roads. I did spend nearly $300 in gas for the week. The handling is quite impressive given the nice ride. With the 19s it is under-tired, and can benefit from the 20s. Everyone in my family was impressed as well.

19.6 is impressive, I have had smaller much less powerful SUV's that could barely get that on a road trip - had an 08 Toyota Highlander for a bit and it only could manage 19 on a road trip at 75 mph - put my little 5x8 utility trailer on it with a couple dirt bikes and it only could manage 12.5 on a 600 mile trip! Sometimes smaller engines don't = better fuel economy!

I traded in a 2008 X5 3.0si for a 2011 X5 50i. I averaged 18.0 MPG on the 3.0 and was primarily highway. I think I will do just as good or even better because of the 8 speed and the more efficient engine

I guess this is as good a place as any..

Just finished my first long trip, starting out with 1940 miles on the 35i.

Reset the trip computer at the start (which is a nice little feature).

530 miles, average speed of 61 MPH, average of 25.0 MPG.
And if I had any reason to doubt it's accuracy.. I got 515 miles on a single tank of fuel.

Trip was through NC, up briefly through VA and through W. VA to central KY, with a long stretch of somewhat steep grade, which this car handled without so much as a slow down.

I think it's amazing - this kind of performance with all-around excellent fuel economy. Not just "excellent for a performance vehicle," just flat EXCELLENT.

The 265 HP GX470 this replaced got about 18.5 MPG (so it said) on the same trip, and could only get about 350 miles on a (one gallon larger) tank.

So far, all is well. It has actually developed that annoying startup rattle others have reported. I'll go hunt down that thread.

Fuel consumption will decrease as the engine breaks in further. Expect to see the best numbers after 15000km or about 10000 miles.

It is not always the most efficient to drive in the top overdrive gear when ascending longer or steeper gradients, that's why the transmission will drop down a gear or two and hold it until it levels out. Although the engine may be able to pull through in top gear, the driver has to push the throttle pedal much harder to compensate (kind of like lugging at too "low" a rpm), and thus consumption may be higher than if the engine was in a lower gear with higher revs, but less throttle.

For example, my X3 often drops 5-4 in the hillier sections of the Piedmont and mountainous stretches of VA. I *could* do many of the highway stretches in 5th, but would have to nearly floor the throttle. Better to just let the AT do its thing. On even steeper gradients (8% or greater), the transmission kicks down 5-3 and holds 3rd at 5000+rpm, does it for miles until the road levels out.

On the wonderful backroads and mountain passes in WV with a 10% gradient, it just dropped to 2nd gear at lower speeds and held it until the redline.