A couple of months ago I left Lake Tahoe and traveled down to the west to Interstate 5 to return home in So. Cal. The first 50 or 60 miles are all slightly or moderately downhill. During that stretch I got 36.5 MPG! After I returned to the flat highway reality set in. But it was fun seeing that kind of mileage for a little while.

 

2011RX350 FWD with crossbars, 20.5 Average, Regular Gas

 

My wife drives our RX we've never checked the mileage.
I cringed when I saw your initial "test" numbers.
Back in '03 I bought a new F250 4 X 4, 4 X doors, 8' box & a V10 gas engine to pull our new 31' travel trailer.
7mpg with the trailer fully loaded, 7 mpg without the trailer, 7 mpg uphill, 7 mpg downhill with a tail wind........etc..
Had an overhead console & a small display centre showing mileage. I kept it on Metric to show a substantially higher number @ 22 l / 100km. Talked myself into believing it was really mpg & felt better about it !

 

we must be back on winter blend gas because Im getting horrible mpg numbers this week. hovers around 23....

 

2015 RX350 AWD, first 400 miles has 16.3 in average, with 87 octane; 50/50 highway/city; any suggestion on improving it? thanks!

 

Adding more miles usually helps.

 

MPG tips:

I get pretty good gas mileage in my 2014 RX350 AWD, (24 MG combined average measured) after 1 year of driving. Right around the 6,000 mile mark I began to see a couple MPG increase, either due to break-in, the computer learning my driving style or a combination of the two.

I drive with a light foot and I mentally drive well ahead of where I am on the road. Like the UPS guys, I plan my routes to minimize road time, start/stops and time idling at red lights. If I'm frequently on a familiar route, I learn the traffic light timing and drive accordingly to avoid or minimize stopping. I'm not a hyper-miler but I do tend to think about MPG as a challenge when I'm driving and this tends to alter my driving style somewhat.

 

Since my last question about what grade of gas to use, I have filled up my 2010 RX 350 twice. I have been using the middle grade gas. I'm averaging 20-20.9 mpg. I haven't used the lower grade yet. I'm liking how the car runs at this time. I might try to use the lower grade when the weather warms back up.

I really keep an eye on the display that lets you know how many mpg you're getting depending on your driving style. (lead foot as opposed to light foot) I really needed this tool! I find that I can go 85 mph to get to my exit only to miss the light and have the people I zoomed by come right up behind me. Plus, it does make for a less stressful drive when you actually drive like you have sense. (and cents!)

 

I wish I could get more than 17.1 on my 2013 RX AWD. Nothing I do including thruway or city driving changes the MPG. Love the car. Best I ever leased. Just wish I had gone the extra couple bucks and leased the hybrid. Lease is up next Oct. My new one will be the hybrid.

 

....and you will love it. Our 2015 450h is only a week old but with a combination of city and highway driving, never went below 26.5 with the low grade gas the dealer put in it. I filled it with 91 a few days ago and almost instantly, it is hovering around 28 mpg. We are totally impressed with it.

 

You sold me. We love everything about the RX. Best SUV on the road. I just hope they don't ruin it when they go to the extra row of seats. It's only me and the wife. We don't need or want anything larger.. I don't want the new smaller SUV either. It's only the size of a Rav four. I'm kind of thinking a end of year lease next Sept. Should still have a selection of hybrids to choose from.
X

 

Just switched to 89 today from regular gas (didn't realize in the last few weeks with my 3RX that I was supposed to use more than regular!) - immediately noticed a difference in mileage. I'll be trying premium next fill in hopes of seeing an even bigger difference

 

my mpg`s took a big hit with this winter blend junk. went from 19.5 down to 17.5... thanks feds! thanks a lot

 

After a 150 or so more miles on this tank of 91 octane with mixed highway/city driving, it is now bouncing between 29.2 and 30.1 mpg.

 

Interesting. I t thought the 2015`s only required 87 octane?