jlim0930

yeah thats what I was afraid of also... hence wanting to get a 350h loaner to drive for a bit so that I can see if its my driving style that is causing this or if its just my car then I would have something more solid to get back to the dealer with.

Highly doubt that its my driving style.. I drive pretty slow and and always watch and make sure that the meter stays near the ECO area

LiBeRtAs

One sure Fire Way to get crappier mileage is have the 20 inch wheels which I do, but I can’t imagine it being more than about a 10% reduction in mileage over the 18 inch wheels.

jlim0930

hmmm I have 20s also.. wouldn't bigger wheels help improve mpg? but I seriously doubt it'll make that much difference

LiBeRtAs

no bigger wheels definitely make it worse. I’ve done the research and like I said, I am allowing 10% but any more than that is unreasonable I believe.

lesz

Regardless of whether you have the 18" wheels or the 20" wheels, the total diameter of the wheels plus tires should be virtually identical. The difference is that the tires that come with the 20" wheels are lower profile tires, and those lower profile tires make up for the 2" difference in the wheels.

Based on the tires used with each set up, one might have tires with better rolling resistance, but, otherwise fuel economy should be very close. Other factors would be much more important in causing differences that some people get in MPG and what other people get. Those factors include driving style, ambient temperature, tire inflation, where one drives, whether most trips are shorter trips or longer trips, etc.

LiBeRtAs

36. In each tire, 60° outside temperature, very little traffic, driving it as slow as possible on the battery as long as possible and I get 35 miles per gallon.

I had a identical car as a loaner for one week with 18 inch wheels and driving the exact same trip the exact same time of day the exact same driving style exact same traffic 45 to 50 miles per gallon

I do what has come to be known as hyper miling as much as I can so my mileage should be much better than 35

jlim0930

im sure your driving style was similar in the loaner vs your own so why the difference? it would say that there was something wrong with the car.

I am in DFW area and its mostly flat and our temps been in the 70s... on highways i got ~28 and on city i get 33.7 +/- 0.2 max. even when the car is warmed up or not... definitely something is not right. proving that something is not right to the dealer is the hard part.

LiBeRtAs

part of the problem is people coming onto message boards and saying they get really high mileage that maybe they do maybe they don’t, I proved that you can get really high mileage with the loaner and the only difference is the wheels so I don’t know.

frustrated

jlim0930

im sure theres some bloating when ppl post but not by that much.. also https://www.fuelly.com/car/lexus/nx350h/2022

just wish that there was a way to find out what might be the issue.....

ViMat

I have done about 7 trips to the cottage with my 350h, 20'' wheels.
Trip to the cottage is about 120km: 60km highway (120km/h), 50km country roads (80km/h), 10km city (60km/h)
My experience is that to get better mileage I have to put an effort and drive the car carefully, accelerating very slowly and trying to "glide" as much as possible. Driving 120km/h on cruise control usually gives me the worst mileage.
Best mileage while driving to the cottage: 5l/100km (47 MPG). I put an effort to safe that trip, gliding a lot, there was decent traffic on highway, so <100km/h speed. With normal traffic I would just annoy to many people driving like that, so not sustainabe.
Worst millage: 7l/100km (33.6 MPG)
Average mileage: 6.1l/100km (38 MPG)

LStoneX

I totally agree with you that 120km/h on cruise control doesn't seem to get great mileage on the highway (I average about 7.0L/100km when doing that).

However, I love me my adaptive cruise control! So a good compromise is to keep adaptive cruise on but set my speed for 105km/h. I find I average between 5.9-6.2L/100km when I drop cruising speed to that level. Which is good enough for me. When I need to pass, I step on the gas, go around and drop back to cruising speed. And if I'm in a hurry, then mileage is the least of my concerns and I'm flooring it🤣😜

Ultimately, do what works best for you. Right now it's no big deal for me. If I was getting 8L/100km or higher, maybe them I might be perturbed.

Right now, it's all zoom zoom baby!

mbezzo

Can't recall where it is offhand, but there's a setting to make the cruise control recovery less aggressive. I've JUST found this setting so don't have any data yet, but I expect it to GREATLY increase the mileage when using adaptive cruise control. I'd definitely recommend hunting in the settings and change it. The car now is much slower to speed up given the opportunity, and is just smoother in general which I think should definitely help with efficiency.

LiBeRtAs

Already on it, but thanks. Can’t use any cruise and get decent mileage, unfortunately.

melissa703

im getting almost 38 mpg average and I got my 2022 NX 350h back in October. Just last week I finally started playing around with ecomode. I use it for when I’m going under 35 but switch out otherwise due to the slow pickup in eco. I do find I have better mileage per trip when I use it.

LiBeRtAs

thanks for your input, I’m getting over 40 miles to the gallon in town when I am very very careful.