Gas Mileage On Your Rx400h

[patt]

My battery has never died, so I'm sure TSIB EG010-05 has never been performed.

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Right, but the battery may have died during shipping and needed to be jumped then. You might ask if the dealer would give it a try.

On a recent trip to the Bay Area, we got 27 MPG even on the return trip when the temperature was over 100 degrees. That was on freeway most of the way, 60 to 70 mph. Unless you are always doing short trips or really bad traffic, you should see better than 24 mpg for some kinds of driving.

[jj_fender]

There is a big difference between averaging 24.6 MPG as you are and never getting more than 24 MPG as Judy reports. Averaging 24.6 may be consistant with the EPA MPG numbers depending on how different your driving is from the EPA city and highway numbers. I get the EPA numbers when I drive something close to the EPA profiles. Our average over the life of the car so far is just over 25 mpg though that includes using AC .

By the way, I have found that painfully slow starts don't seem to be the best thing for mileage. I get as good or better mileage when I go fairly promptly up to speed and then cruise. And why would you spend 50K to drive a car where you can't use the air conditioner?

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Thanks for the reply Pat and the advise about the slow starts. I don't quite understand what you mean by a "big difference between averaging...and never getting...." Isn't the EPA some kind of average. My average just happens to be over more than 1000 miles. Anyone can get EPA MPG numbers or above on a particular trip. For instance, when I first reset my average MPG (actually the only time I have reset it) I went to my mom's house (mostly downhill or flat) and averaged 36 MPG. But that is meaningless. EPA estimates should take into account a variety of driving conditions over a considerable period of time. Not just one or two trips.

[patt]

jj, You can find out about how EPA tests are done here:

http://www.fueleconomy.gov/!Removed!/ratings_description.shtml

There is no way to get a number that will be what everyone sees as their long term average mileage. That will vary between people because driving styles and the profiles (% freeway, % surface street, exact type of city driving, length of trip). What the EPA numbers are suppose to be are numbers that are tested the same way on every car to provide a relative measure by which the fuel economy of cars can be compared.

The fuel economy test schedules item on the site above will tell you the driving conditions for the EPA tests.

What I meant about the difference between an average of 24.6 vs never getting more than 24: Our life time average so far is a little over 25 MPG. That includes extended periods when we have gotten 26 to 27 mpg and another where we were averaging 22 mpg (a lot of short trips - the worst thing for mileage). Not surprising given the wider variety of our driving compared to the EPA test conditions and the fact that EPA tests don't include some factors that reduce mileage like loads from accessories (e.g. AC). On the other hand someone who never gets more than 24 mpg is probably also running over a range of mileages and their average is significantly below 24. Either they are always driving in worst case conditions in some way (which seems unlikely to me since I easily and repeatably get 26 to 28 in freeway cruising) or there is something wrong.

[thesaintjim]

I have a question for all of you. I noticed when I use cruise control, my average drops compared to when I do not use cruise control. I am averaging 28.0 mpg now. Does anyone else use cruise? Does it drop your average?

[katzjamr]

In my experience cruise especially on a flat road increases mpg. The car seems more in tune with itself and is quicker to coast. I dont know if this is true for all cruise situations.

[thesaintjim]

In my experience cruise especially on a flat road increases mpg.  The car seems more in tune with itself and is quicker to coast.  I dont know if this is true for all cruise situations.

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Yeah, I travel on hills/mountains, so, I am sure that must kill the cruise control then.

[jj_fender]

jj, You can find out about how EPA tests are done here:

http://www.fueleconomy.gov/!Removed!/ratings_description.shtml ...

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Thanks again Patt. I did check out the EPA site and found that it is very informative. One thing that I had not considered is the differences in fuels. Here in California, they add all sorts of things to the fuel which raises the cost and probably lowers mileage.

The EPA says that they used real drivers to simulate different driving conditions in the city and highway. If that is the case, they should be pretty close to real driving. However, they only test about 15% of the cars themselves. The other numbers come from the factory...hmmm. The test drivers at Lexus supposedly got 30 MPG driving in "city" conditions. It would be interesting to hear from the Lexus people about how they accomplished such an incredible feat. Again, as hard as I try, I am only getting 24.7 combined city and highway...about 20% lower than those amazing factory drivers.

[HyBruce]

Okay, I'm on my 3rd tank of gas... 600 miles on the car.... and on this tank I'm averaging 17.8 mpg!

Now it's been in the 80's/90's here in SoCal, so I've been using the A/C most of the time... And my commute isn't that long, so my average trips are like 15-20 minutes... but less than 20 MPG?? My first few tanks i was getting like 21 mpg.

Do you think that the TSIB issue could really be my problem? Do I need to take it to the dealer for that?

Or is it just that my car is still getting used to itself?

Anyone else getting that poor mileage?

Other than that, I LOVE my 400h!

[katzjamr]

Welcome Bruce, if your figures are accurate you may at least qualify for some kind of award for lowest mpg. Seriously, as you must already know there is alot of feedback available to you on the nav consumption screen and below the speedo. Make an effort to modify your driving based on what you see on those meters, there is no reason you shouldnt be getting a consistent 24 to 27 even with ac on.

[indiasfinest]

in my personal opinion you shoudnt have to change your driving styles to achieve the MPG you want....if the EPA hired grandma's to test drive these cars its not my problem....but they should atleast make the rating more accurate...this car should meet my needs not the other way around....even if i dont have a 400 i still think this is wrong...my GX get 17 MPG sometimes....this is pathetic

[katzjamr]

That is all well and good india, however obviously driving styles make a difference even among traditonally powered vehicles. Prius drivers found out along time ago there were skills they had to learn to make their cars more efficient if they chose to do so. I have had to retrain myself when i drive this hybrid, and its made me a better driver in all my vehicles. just my 2 cents.

[patt]

Okay, I'm on my 3rd tank of gas...  600 miles on the car....  and on this tank I'm averaging 17.8 mpg!

Now it's been in the 80's/90's here in SoCal, so I've been using the A/C most of the time...  Any my commute isn't that long, so my average trips are like 15-20 minutes...  but less that 20 MPG??    My first few tanks i was getting like 21 mpg. 

Do you think that the TSIB issue could really be my problem?  Do I need to take it to the dealer for that?

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18 MPG or even 21 is pretty poor MPG. Maybe if your commute is 15-20 minutes creeping along in stop and go. If 15-20 minutes means 8 to 15 miles, I would expect to see better numbers based on the experience I'm having with mine - maybe at least 24 or 25 mpg. It seems like the TSIB might be your problem, but there is only one way to find out - get the dealer to try it and see if it makes a difference.

I'd really like to hear the results of someone with low mileage taking it to the dealer for the TSIB.

Driving style does make a difference, but unless it is really poor (so that you would get poor mileage on any car) I don't think it would pull things down that low.

[RolandB]

Sad performance for the past 6 months:

Date Mileage MPG

05/03/05 280

05/10/05 546 22.27

05/20/05 866 22.89

05/28/05 1,100 21.38

06/05/05 1,409 21.95

06/17/05 1,715 21.14

06/22/05 2,026 22.32

07/01/05 2,307 21.06

07/13/05 2,589 21.00

07/18/05 2,840 21.31

07/30/05 3,137 20.04

08/08/05 3,400 20.09

08/12/05 3,496 22.18

08/13/05 3,773 24.13

08/15/05 3,847 18.18

08/15/05 4,174 23.16

08/21/05 4,417 20.38

08/29/05 4,696 19.83

09/05/05 4,910 21.04

09/12/05 5,139 19.98

09/22/05 5,432 20.55

10/04/05 5,728 21.66

10/16/05 6,023 21.72

10/23/05 6,265 22.95

10/30/05 6,468 23.30

11/07/05 6,680 23.66

11/14/05 6,921 23.58

Almost all of this is in town driving! These figures are calculated since the car's indicated MPG has always been 1-2 mpg greater than actual. As you can see, MPG seems to be on a rise! Interesting thing I have observed relates to cruise control usage. My wife only uses it on the freeway whereas I use it always when it is safe to do so! She seems to get better results on the indicated MPG. Hmmm, maybe her foot is better on the car than the Cruise Control??

Roland B.

[bainse]

Someone knowledgeable about these sorts of things should maybe re-post this poll. I voted when I first got the vehicle and was getting 22 MPG; now after 4 months and about 4,000 miles I'm getting 26-28 MPG but can't change my vote. : )

[woestehoff]

I purchased my RX400H in June. It now has 6500 miles. I'm probably averaging around 28-29 MPG. In the summer, I was averaging around 30.5 MPG. Now I'm getting 27-28. In the winter, they change the fuel mixture to include MTBE. The colder weather and the MTBE does seem to negatively affect the mileage. I do use premium gas and I know that has a positive affect, probably 1-2 MPG. I don't have a lead foot and I coast whenever possible. I live in Colorado where we have mild summers so the air conditioner is not used extensively. But in the hottest time of the year when it was on most of the time, I did not notice any difference in MPG.

Here's the really interesting thing... We took a short vacation with 3 people and the RX400H filled with luggage. We drove over multiple high altitude passes. Total miles ~640. I filled it up at the start and reset the gage. I filled it again after about 400 miles. By the time we got home, we averaged 31 MPG. On the passes I could coast downhill for 20 miles. But going up the same passes, the gas engine was used extensively for the same 20 miles. The air conditioner was rarely used on that trip.

When I signed up for the waiting list, I was hoping for 30-35 MPG. But 29 is still a big improvement over my previous vehicles. And the performance and luxury is top notch. All in all, I'm very happy.

Keith

[jj_fender]

Sad performance for the past 6 months:

Date    Mileage      MPG

05/03/05      280

05/10/05    546 22.27

05/20/05    866 22.89

05/28/05 1,100 21.38

06/05/05 1,409 21.95

06/17/05 1,715 21.14

06/22/05 2,026 22.32

07/01/05 2,307 21.06

07/13/05 2,589 21.00

07/18/05 2,840 21.31

07/30/05 3,137 20.04

08/08/05 3,400 20.09

08/12/05 3,496 22.18

08/13/05 3,773 24.13

08/15/05 3,847 18.18

08/15/05 4,174 23.16

08/21/05 4,417 20.38

08/29/05 4,696 19.83

09/05/05 4,910 21.04

09/12/05 5,139 19.98

09/22/05 5,432 20.55

10/04/05 5,728 21.66

10/16/05 6,023 21.72

10/23/05 6,265 22.95

10/30/05 6,468 23.30

11/07/05 6,680 23.66

11/14/05 6,921 23.58

Almost all of this is in town driving!  These figures are calculated since the car's indicated MPG has always been 1-2 mpg greater than actual.  As you can see, MPG seems to be on a rise!  Interesting thing I have observed relates to cruise control usage.  My wife only uses it on the freeway whereas I use it always when it is safe to do so!  She seems to get better results on the indicated MPG.  Hmmm, maybe her foot is better on the car than the Cruise Control??

Roland B.

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I completely agree with these figures. I have had my RX400h since April and have had almost exactly the same results. Makes you wonder about those people who claim to get 30 MPG. I don't believe them.

[davetroup]

I've been getting between 23 and 24 mpg, but I live in San Francisco and so I traverse a lot of hills. On longer freeway trips it seems to average around 25.

My biggest gripe is that it's basically impossible to use the full potential of the hybrid system. I'd like to be able to drive around town (on flat terrain, at least) and rely almost exclusively on the electric motors. But the acceleration is so painfully slow until the gas engine kicks in that other cars have actually honked at me in impatience. I finally have given up on trying to drive economically and I just drive. Of course, this makes the mileage even worse.

I really like the car, and I've put a couple thousand miles on it at this point, but I do feel that Lexus sold people a bill of goods on the mileage claims. Having said that, I'm sure the mileage is much better than a comparable non-hybrid SUV, which is what attracted me to it.

[RX400h]

To put things in perspective, the new Mazda 5 mini-minivan, which weighs 3100 lbs, averages 23 MPG - considered quite good for a vehicle of this weight.

[400h4me]

We are very pleased so far with the gas mileage. When I drive I can average better milegas than my wife does. My wife commutes 220 miles round trip to work.

Going to work is mostly flat with some downhill driving mixed with uphill. Daytime tempertures average 50-70%. We live in Northern California pass Santa Rosa and my wife works in the SF. bay area. She has been averaging between 26/27 miles per tankfull. I made the same trip last week by myself and checked the mileage.

Going down to the bay area "driving under 65" was better than coming home later that night. The mileage was 28.9 going and 26.7 coming back. We use to do the same trip with a 1995 Ford Explorer and the average was 18 so we are very pleased! :)

[SixEcho]

I normaly get high 20s, but if I try hard enough

[RolandB]

As the odometer approaches 10,000 miles, I thought I'd update my 'MPG' findings! One big observation has had me conclude that while the RX400h's MPG calculator is better than none, it is usually 1.5 to 2.5 MPG too high! (5 - 10% variance) My spread sheet says the best I have ever achieved was 25.49 MPG and that over the lifetime of 9,494 miles, I have gotten 22.18 MPG. Conclusion! Do your own calculations for a few tanks and see what you are actually getting and then you can mentally apply an 'Indicated' correction to make your judgements!

Because of formatting problems, I decided not to post the spreadsheet but may reattempt at some time in the future.

[wstr75]

As the odometer approaches 10,000 miles, I thought I'd update my 'MPG' findings! One big observation has had me conclude that while the RX400h's MPG calculator is better than none, it is usually 1.5 to 2.5 MPG too high! (5 - 10% variance) My spread sheet says the best I have ever achieved was 25.49 MPG and that over the lifetime of 9,494 miles, I have gotten 22.18 MPG. Conclusion! Do your own calculations for a few tanks and see what you are actually getting and then you can mentally apply an 'Indicated' correction to make your judgements!

Because of formatting problems, I decided not to post the spreadsheet but may reattempt at some time in the future.

Roland,

Like you, my actual mileage is averaging about 1.5 mpg less than what the 400h's screen indicates. My 400h has 1600 miles and is averaging 23.5 mpg in about a 50/50 mix of short city trips (some of it from home to work = 2.5 miles and the ICE runs the entire time). The gas mileage on the road holds steady around 26 - 28 up to about 68 mph. Above 68 mph it starts falling off.

[Still]

I normaly get high 20s, but if I try hard enough

I have accomplished this feat once also. It was exactly 38.0 - granted it was on "a trip down off the mountain" (about an hour and a half), but it wasn't all downhill! I got about 27.5 coming back, so that still averages about 32.75 for that particular trip. One the whole I'm averaging about 28 even when I'm not trying. Now if I could just get this tire thing figured out. <_<

[Still]

I normaly get high 20s, but if I try hard enough

I have accomplished this feat once also. It was exactly 38.0 - granted it was on "a trip down off the mountain" (about an hour and a half), but it wasn't all downhill! I got about 27.5 coming back, so that still averages about 32.75 for that particular trip. One the whole I'm averaging about 28 even when I'm not trying. Now if I could just get this tire thing figured out. <_<

[shooterjz]

So far I've noticed that my MPG is about 26-28 ... good enough for me on a SUV ... anyone know what's the ave. reading on a Rx350 for MPG ?