PeeVee

Try resetting as you arrive to a red light, see how it goes down dramatically while running idle. It will slowly go back up as you start rolling again after the green light. That idle time seems to be costing a lot on the MPG calculation.

DMPesso

Figured you guys would find this funny. Just reset it coasting down a hill. If only this was actually possible. I only get about 14 MPG in my 2017 F Sport with a lot of stop and go NYC driving and a lot of idling. I guess that’s normal with these wheels and NYC.

milk659

In a best case scenario, I have seen 26-28 MPG on highway when outside temperature is in 60-80F, and I drive it on cruise control with very little traffic. Lower temperatures and any time you slow down and accelerate later, eats up MPG. Harder you accelerate, lower the MPG. In worst case scenario, city driving, below 0 F, I get 16 MPG. (I am sure I can make it worse by pushing it more). All using 87 Octane gas.

I have experienced rattling issues from the very beginning. Some fine rattle from this window, or the hatch, or the dashboard. Wasn't able to find any solution to rattles other than "Live with it"

2017 RX350 AWD Luxury Package

kg11

30. miles per US gallon. Highway summer. About my peak fuel economy.

Also, at very specific temperatures I seem to get a small ticking rattle at the upper left side. I have the same in a 1988 highlander. I suspect air bag wiring is just vibrating a bit. Noise rarely happens.

1halifax

My 2019 350 gets 18 mpg mostly city driving. It seems low. Is there anything the dealer can check?

ravenuer

I doubt it, assuming you live in Nova Scotia, city driving, you're right on target.

rpetruzz

Just purchased my 2020 RX 350 Luxury package and took delivery 11/272019. Since day 1 of delivery my gas mileage has been averaging 13-14 mpg. Even on the highway I seldom get more than 16.2 mpg. Had the dealer check it out yesterday and I was told that all sensors showed the engine was functioning according to specifications. Nothing found that was wrong. They told me that it was because I'm retired and I drive short trips around town and infrequent trips. Also that here in Connecticut USA we are in winter and the grade of gas was "winter grade". That it will be better in warmer weather. I find this challenging because I just traded in my 2017 RX 350 Luxury package. Identical to my 2020 in features. In it I never got lower than 16+ mpg in winter and my driving habits haven't changed. In summer I got around 19 mpg. That was as expected. I'm going to be sorely disappointed in this vehicle if the mileage isn't going to be at least as good as my previous 2017 RX 350.

ravenuer

Your car is still pretty new. I'd make sure the tire pressure is at least what's on the door sticker. I set mine a pound or two over that when they are cold. Are you relying on the dash indicator for your mileage? If so, check it using the "pencil and paper" method for a few tanks. I think your new car will eventually settle in where the old one was.

rpetruzz

Hi ravenuer , thank's for the quick reply to my message. I didn't mention, that when I picked up the car, the tires were at 40 PSi. The door calls for 33 PSI so I've lowered them to 34-35 PSI and when cold the dash gauge shows them to be around 33 PSI. Also, I didn't mention that I always reset Trip A every time I fill the tank and the mileage I'm referring to is from my manual calculation based on the miles traveled in Trip A / Gallons pumped. I also didn't mention that after 2 months I have < 600 miles on the vehicle. The dealership also said it should be better over time. So your thoughts add some comfort to my angst. Thanks again..

ravenuer

Ok, you've seem to have covered all my suggestions! The only one left is...…..time. And miles...…!
BTW, I'm a snowbird, NY to FL in the winter. In summer, I don't use my 2017 RX350 much. I have a RAV4 I use for most of the local driving. Use the RX only for trips etc, so I average 19-20. On the way down to FL, I get 26-28, with the cruise on, averaging about 70-75 mph. Now that I'm in FL and using it every day, I'm averaging 16, worse was 15.3!
As they say, YMMV!

rpetruzz

ravenuer: Thanks again for your insight. I'm hopeful that over time as I build up mileage the fuel mileage will improve. Rather hear it from someone who owns one than from the dealer service.

DMPesso

Sounds about right. New cars usually get about 2 MPG less until they “break in” and learn your driving habits. You should see an improvement over the next couple thousand miles. However, did you have smaller wheels on your 2017? Wheels can change the mpg if you got the 20” wheels on your 2020 but had “18 on your 2017. My f sport gets horrible mpg - 13-14 MPG city driving in Brooklyn.

rpetruzz

Hi,
My 2020 Lexus is feature for feature the same as my 2017 except for the color. 2017 was Silver LIning Metalic and this 2020 is Nebula Gray Pearl. Other than the changes that Lexus made to the Nav system and the car's physical profile. 20" tires on both of them. But, thank you for your reply, it's good to know that once I get by the initial break in I should see improvement. I guess some of this is my own doing. I've had it 2 months and only have ~600 miles on it. Since I retired I really don't drive as much as I used to and I do use the remote start a bit more in the winter. What had me concerned is that my driving habits in my 2017 were pretty much the same and I was getting better mileage. Had that for 3 years and only put ~18,000 miles on it.

GSFRX350

As other have said give it time, 600 miles is nothing and you're only talking about a few mpgs.

rpetruzz

Thanks very much.......