sunnyside

We have a 2013 RX450H with 103,000 miles on it. We live in the hills of North GA and the car delivers about 28 mpg. I get the same on the road running at 70-75 mph. Above that there is a penalty and the mpg drops off. On flat ground in FL I have seen 33 at the same speed. The car will be due for the major service soon and we intend to keep it long term. I suppose there could be a slight improvement with new plugs. l use an injection cleaner about every 5,000 miles and have an AFE Power acrylic air filter. The car started life with Dunlop tires. It is on the second set of Michelins and there has been no difference with the tires. My other car is a 2014 RX 350 and the milage is around 24-25 in the same area. The hybrid is my wife's car and I really like mine better with the 6 speed transmission.

MellonC00

Little more than 5% drop in MPG. It went from 25.5mpg to 24 mpg. My daily commute is exactly the same. Though I must admit that my avg speed has gone up from somewhere in the mid 20s mph to mid 30s mph due to not many people being on the road.

NickSP

Even my drive is quicker now with less traffic. I've learnt from driving the Prius that accelerating quickly and reaching a cruising speed is the best for a hybrid.
Your drop in mpgs sounds normal given your increased speed but try to get to that speed quickly.

knudtl

I’m at 96K AWD 2011 RX 450 H in Denver, i am so disappointed in the gas mileage among among other issues. i get under 27 mpg.

knudtl

For me my 2011 RX 450h mileage is poor 25 mpg! Lots of other major issues to.

Droid13

Usually I manage to get the best "full tank" fuel economy around this time of year, in late summer or early fall, not sure why. Maybe the mild temps I don't need to use A/C or heat, but oddly in spring with temps around the same I just can't get as good fuel economy. Maybe its the quality of seasonal gas, idk. Anyway, I usually like to attempt a new tank record around now, but I've had quite a few out of town highway trips this year which always negate any shot at a record. I usually end up driving kind of fast. I thought a couple weeks ago at my last fill this would be time for this year's attempt, no pending trip plans, just around town driving, taking it calm everywhere I went but alas the gas needle took forever to move (usually great, but in this case ) and now I have to go out of town again. Probably going to be too cool temps coming for another record shot this year, so there I stand... Almost half a tank used at 7.4 (31.8mpg) I was just a little off my record hoping I could still squeak out a bit better the bottom half. Until next year...

LOL, too calm for one driver a few days ago, I was just a tad over the speed limit holding my sweet spot, he pulls out and races by, 10 seconds later I see the cop walk out into the street and wave him over.

Miketup

My 2010 rx 450h may have a problem. 23-24 MPG with 122,000 on the odometer. I should be getting 29mpg. I may do the plugs but I am afraid it may be the hybrid battery.

NickSP

Sorry meant to ask this in the 4 RX from.

Hamsnacks

Hello,

Purchased a 2010 RX 450h with 125 000kms. It wasn't a daily driver, 60 year old who used it on the highway in the summer for long trips.

I've read several posts regarding Milage and I'm pretty sure I just got a unit that isn't that fuel efficient as others but it's actually really bad. Winter right now, I may get 400kms max on a full tank, something like 15mpg. It's almost equivalent to my Escalade (6.2L V8)

Is there anything I could replace mechanically that may be causing it? Neighbor suggested Spark plugs, but so soon?
I know the service says to replace the 2 coolants right now, but they look brand new, clean in color and full. Any other suggestions, no jack rabbit starts, drive in eco mode, let go of the pedal early, minimum braking.

I don't need 30mpg but mid 20s would be nice, just very surprising. Going to do an oil change this week and reset the fuel consumption and monitor.

Should I replace the coolants if they both look good?

Thank you

05RollaXRS

Winter driving is a big factor. Driving with the heat, heated seats etc. on and how we have to drive over snow and ice etc. affects MPG. As soon as the snow in early November, I saw a decrease in MPG in my 2014 RX450h like I do in my other cars (previously RX400h and the Corolla XRS). Now, I am around 10 liter/100 KM, but when I purchased the car in early November when the weather was decent, I was able to get around 8 Liter/100 KM if I did not go in sport mode and used ECO mode primarily. The screen shows a peak of 6.7 Liter/100 KM and I am averaging 9.8 Liter/100 KM these days.

yeehawbob

Have you checked your brakes, especially the parking brake?
10 year old car that was not driven much so it was always parked with parking brake engaged so it may be causing drag.
Without starting the car or in EV mode roll it on a gentle slop and hear for any friction.
Just a thought!

Droid13

That is terrible. That would be like 15L/100k (another one of those rare cases when the US measurements match metric, and its never good when that happens). I can't think of anytime I've seen that, maybe driving 150kph while its -20C outside. I can't see it being spark plugs or ignition unless you're noticing rough running. Engine power seem ok? Maybe try a few tanks of high detergent premium fuel, or possibly have the injectors cleaned directly?

I like yhbob's suggestion, check to see if brakes are dragging somehow. I've found on mine the back brakes do need service regularly to keep them moving freely as they don't get very much use, as I assume you have the Canadian model too which all have regen braking on the back.

As for coolant, sure why not. If you don't think its been changed its not terribly expensive to just do a drain and fill at the right place, or doing it yourself.

Mbnaro

Just bought my first RX 450h AWD, 2010 model with 93k on it. I picked it up today from dealer and had a full day to drive around town.

If I let off the gas it does not coast at all. It slows down very quickly after I take foot off of the gas and is very strange to me. Also it has a minimal whining noise when driving which dealer says is normal to add sound for the hybrid version so people can hear you coming. ? Also I looked up the MPG log from back in 2012 and the highest avg I've seen it get is 22- rx450h normal????
23ish mpg. This concerns me as well. I thought It was rated 30 highway and 28 city.

Please let me know if this sounds normal to you guys.
Thanks

COPAPILOT

This one looks like it was driven by a lead foot. The slowing down when you lift your foot of the gas is charging your battery as you drift to a stop when you see the light is red ahead. Pushing lightly on the brake will also charge the battery and not wear your mechanical brake pads. On starts just bring the indicator out of the energy saving range and allow it to return into the energy saving range while crazing. This will get you up into the 30s around town except during cold weather and on winter gas mix. Since the RX450h adjusts it engine to the gas octane used, you can use regular with no issues or power loss. Use a good gas brand like COSTCO, Shell, Mobile or BP. Any that have the altra-filter on the pump. That will keep your valves clean.

Once you learn to drive a hybrid it becomes natural and you will enjoy the RX450h. Very reliable.

fishybone

If you live in a hilly area, it’ll really impact your fuel economy too.