lexus114

go by the mpg after re fueling, much more accurate. or reset the regular mpg read out ounce in a while. also i have noted a 1 mpg + difference on 89 octane over regular fuel. and the motor pulls better and the trans doesn't hunt for gears near as much either. overall a better smoother driving experience over the regular.

jfelbab

In my experience with my old 2004 RX330 and my 2014 RX350, the computer monitor is not all that accurate. Record the miles you travel between fill-ups and divide that by the gallons used to get more precise MPG values.

coachlkg

Always the best way for accuracy, but too much work for some.

I just drove my 2013 RX350 AWD from Indianapolis to Orlando and back. I got 22.7 mpg (95% Interstate).

jfelbab

In January, I drove my 2014 RX350 AWD from Milwaukee to Cape Coral FL, 1384 miles, 55.8 gallons, average 24.8 MPG. The RX was heavily loaded. 100% interstate and mostly cruise set at 75 MPH. I used mostly Shell 87 octane E10 regular fuel this trip.

Looks like I need to make this same trip a three more times in the next few months so I'm anxious to see what the fuel economy is with no winter blend gas and warmer weather. Overall, I've been relatively satisfied with the expressway fuel economy of the Lexus RX. Driving around Cape Coral and Fort Myers the fuel economy dropped to 21.7 MPG. I can't believe how long the stoplights take to cycle here in FL. Seems if you are stopped at a red light it stays red for 4-5 minutes. Can't believe how many drivers run red lights here.

JDR76

I used to always check my gas mileage by computing it out, but every time I have, it's within .1 mpg of the dash readout so I don't bother anymore.

On our 2013 RX350 with 15k miles, we're averaging 21.7.

kross871

I purchased my 2015 RX 350 in July 2014 and it has about 3000 miles on it. I recently noticed that the gas mileage is VERY low, around 13 mpg. It is rated at 18 mpg City/25 Hwy for combined 21 mpg. I know there's fudge room in testing but mine doesn't even seem to be in the realm of the margin of error. When I have a completely full tank, the readout says 249 miles to the tank (19 gallons), and I don't even get that much. I admittedly do more city driving than Hwy. Per the manual, I'm using 87 octane gas, and can't imagine (but am ready to stand corrected) that using 89 or 91 would account for a full 5 mpg difference. I am not a jackrabbit starter and can't speed much in the city. I had a 2007 RX 350 that got way better mileage (17 at its worse) in identical driving conditions. My mom got her identical 2015 RX 350 at the same time and in her city, she gets 19-20 mpg, and much higher on the highway.

Seems to me that 13 is very low, no matter what kind of gas I'm using, the cold climate I'm in, and even if I was doing 100% city driving (though it's more like 70%). Any thoughts on whether there might be a problem that I should have addressed? Thanks.

jdshaw

Also have a 2015 RX 350 (AWD) purchased in July. 7,000 miles. I get a consistent 20 MPG city/24.5 highway.

kmar

I've had my 2015 RX 350 for a month with 3 or 4 fill-ups. I'm getting about 16 mpg around town. On one trip which was highway/freeway for half a tank I got 24 mpg (according to the readout on the car). My previous vehicle, a 2008 Hyundai Santa Fe with the 3.3 liter V6 consistently got 18mpg in the city and 24-25 highway, exactly what it was rated at. Hopefully my in-town mpg will get a little better with the new RX.

Marqevans

I'm in Illinois, and have had my 2015 for a 6 weeks . This tank full I am at 17.9 mpg. Mostly suburban driving and no highway. You should probably do a hand calculation because 13 seems really low.

kitlz

Welcome to CL, kross871. There are a few things to consider regarding your low mileage. First would be the cold weather combined with the winter fuel blend. Neither helps mileage at all. You're also within the 5,000 mile break-in period. Your mileage will increase as the temperature and odometer climbs. Give it more time. And be sure to check out the 3RX mileage thread .

kross871

Thanks for the responses. I know the cold affects things, but didn't think it could account for such a low number. I drove my '07 for 7 years in the same climate and never got such low mileage, even in the early months or in its later years (and always used 87 octane, even though back then it wasn't recommended for the RX's like it is today). At the rate I drive, the car will be nearly a year old for me to get through a 5000 mi "break in" period. The dealer agrees 13 is too low but mechanics can't find anything wrong re codes. Just don't know what to do at this point.

kitlz

Keep driving to put on more miles and wait for warmer weather. That's all you can do.

SteveCraig

City driving & local landscape can play immensely into realized MPG. Driving on flat terrain, similar to what I see in sunny Florida, is quite different than our city with many, many hills & the extreme cold.
That said, my F150 4X4 truck with a 5.4l auto averages 15-16 MPG year round. I can approach 19.5 - 20 MPG on the highway if I stay at or just below the limit. Problem is I rarely stick to the limit .
-35 C here tonight with another blizzard due in Sunday.Should see another 30"-35" snowfall.
Gotta live here to get it!

jfelbab

My 2014 RX AWD picked up a couple MPG right around 6,000 miles. Winter blend fuel dropped my fuel economy by 2-3 MPG. I'd still refer this to Lexus on your next service call to get your dissatisfaction on record. If the fuel efficiency doesn't improve there may well be something wrong. 13 MPG is disappointing for sure but I'd venture that when they test for the EPA figures it is not done with winter blend fuel and likely done under optimal weather conditions, not temps in the teens.

My measured fuel economy so far 100% City: 20.5, 100% Highway: 25.3, Average over 16 month: 23.9

cliffinaz

kross871

My wife has a 2013 RX 350 AWD with 19 inch wheels. It only has 2985 miles. I am keeping fuel mileage records (since new) by hand calculation (as opposed to using the trip computer). In all city driving it gets 15.5 mpg. On two all highway trips of 600 miles round trip each, it got 21.2 mpg. On the highway I usually run about 80 mph. In town it is under 45 mph stop and go. Living in AZ the cold temps are not a factor. The place where I refuel is a Chevron that does not use winter blend and I have always used 87 octane. Just wanted to give you something else to compare to.