Lexus RX 400h - MPG-Real World Numbers

oiseauxno

We've got about 4000 miles on the 400h, and had been averaging, here in hellishly hot N.O., in the low to mid 20's. There's been virtually no time the a.c. hasn't been on. Finally, this past Sunday it was cool (using the term loosely) and I drove about 40 miles without the a.c. The first half was with cruise set at +/- 69 mph; the second half was stop-and-go flat city. I figured that between the two, it was pretty durn average American driving. The average was 35.1. I was ecstatic. I'm thinking that Toyota made a terrible mistake by not waiting until fall to introduce the car; they might thereby have obviated a lot of the bad press. The a.c. must really take a toll on the mileage, and I guess it's a no-win situation for them to emphasize that fact...

dreedaz

Filled up today and took care of a few things across town. Went 64 miles and averaged 30.2 MPG. Was at 31.2 but my wife stayed in the car with the air and radio on while I went shopping for groceries. I can't complain about this average.

erno

I also live in Hawaii. Drive in mixed city/highway although Hawaii's Hwys are never really that fast or steady. Live on a hill and go over the Pali (a low mountain pass). Almost always use the A/C. At first I was disappointed with 21mpg. But it slowly rised to 23, 24, 25, 26 with each tank. Now I am trying to get an average of 27mpg with my vehicle mileage about 3000 miles. Every so often , I fall for the temptation of gunning the engine. Since it is so fast. Haven't tried the top speed yet but I have gone over 80mph without noticing.

I'm very happy with the quality of the car. I hope future versions will give you a knob or something to decide on your own tradeoff between power and savings. Also a plug-in kit would be cool

richcbt

I absolutely HATE my RX400h, and have been fighting with Lexus and my dealer ever since I filled it up the first time. I am getting 20.6 MPG with mostly city driving, and have now completed almost 2000 miles.

I traded in an RX 300 which was getting 18-19 MPG with the same type of driving, and I was burning lower octane fuel. Yes, I have followed the manufacturer's recommended 92 Octane, which of course means that my fuel bill is actually HIGHER with this vehicle.

I drive the car normally, and it has been a cool summer here in So Cal so my air-conditioning use is not huge. I rarely have passengers in the car, and do not jam the accelerator except under rare circumstances. Most of my driving is within five miles of home so perhaps the car doesn't warm up a lot, but I do find that it gets much better highway mileage, contrary to the EPA sticker.

This is my fourth Lexus, and I have never had anything but positive things to say about the vehicles, the dealers, the service departments, etc. Now, I've never been more disappointed with an automobile in my life, especially with the cavalier and frankly even rude treatment I've received from my dealer when I tried to bring this to their attention. Just thought I'd chime in here. I consider the vehicle to either be defective, in which case they should fix or replace it, or that Lexus should include a warning to buyers that they should not expect more than around 21 MPG in city driving.

stevedebi

"Most of my driving is within five miles of home so perhaps the car doesn't warm up a lot, but I do find that it gets much better highway mileage, contrary to the EPA sticker."

That is most likely your problem; the HSD is vulnerable to poorer MPG with short trips.

katzjamr

Short trips are a mpg killer on this vehicle, everyone reports this. I try to coast more on short trips and still can average 25. I am getting 26 to 28 in mixed hiway city driving. Perhaps your dealer will trade you for a loaded rx330. The first questions my sales man asked before i even drove the demo were what was my normal driving routes. He was honest about what to expect mpg wise and told me a 330 would be a better option if i drove mostly hiway. Once i drove the 400h i could never go back to a 330. Most of us are using regular fuel and few have noticed a difference with premium. So i would def go back to regular. Over 75% of the 400h owners are reporting 25 mpg or better, there is way you can get those figures if you are willing to learn.

richcbt

I do take a lot of short trips, but over the last 1900 plus miles I've been to Palm Desert from Torrance, up to Ojai, and a few times a week I go somewhere 20-35 miles a way. Last week it was Anaheim and Long Beach, so I'm getting out there on the highway some, which is the only way this vehicle has barely gotten over 20 MPG overall.

The thing is, the sales manager practically hung up on me, and he flat out lied about conversations he claimed he had with me that never took place. I wrote a letter to higher ups in Lexus Headquarters and got a guy calling me who had absolutely nothing to offer. They're making no effort to do anything, even after I told them after 300 miles I did not WANT to pay 10 grand more, buy a lojack, chrome wheels, and every other extra, just to get a mile or two per gallon better mileage from a new RX330. I want them to buy it back from me, and will take the loss, pay for my mileage, etc., and save them the embarassment of the stink I'm going to make if they won't make good.

I have a feeling that they'll one day regret not buying back the car and reselling it as a hot barely used vehicle, rather than having the entire world know that this much vaunted hybrid gets no better mileage than the V-6 they've been offering in the earlier models, at least not to speak of.

I wanted to really feel as though I could own an SUV and not feel guilty for owning a gas guzzler. I think a lot of 400h buyers wanted that, and 20 MPG doesn't cut it. I've threatened to stand in front of the dealers with a sign suggesting that buyers don't buy an RX400h unless they're prepared to be satisfied with 19-20 MPG in the city, and 20.6 overall.

Could I get better mileage by never accelerating, always coasting whenever possible, etc.? Maybe, but I drive it pretty gently. I WANTED to see good numbers. As it is, I feel like a chump, and what's worse is I can't sell it without lying to the buyer. I didn't drive my RX300 that way, and it performed close to EPA specs.

One way or the other, my faith in Lexus as a quality manufacturer with outstanding dealer service is gone completely. There is no excuse for a guy sitting opposite you and essentially treating you like some sort of nut case, when you've bought three prior vehicles from them and never complained!

I'm not normally litigious, but something tells me I'm about to be. You can't just offer customers one type of performance and then when they don't get it, ignore them.

katzjamr

If i could only get around twenty mpg out of my 400h i would be upset too. Are you resetting the mpg readout with each fillup? That will start you with a clean slate with each full tank of gas. Also are you checking this mpg mathematically by keeping a record of the miles used on each tank and how much it takes to fill up? just wondering...

richcbt

I have recorded each and every gallon, down to fractions, that I've pumped into it, and currently the vehicle has had 80.7 gallons put in it, the yellow warning light is on, so when I fill it I will put approximately 15 more gallons in it, and it has 1960 miles on the odometer.

During the first 1500 miles I never reset the on dash mileage display, and it showed a little over 21 MPG. Since I reset it, I've driven over 400 miles and last I checked it showed 20.1 MPG. I was told, among other things, that the car could still be breaking in, but the mileage has actually gotten slightly worse over time.

I found this forum because I was suspicious, by how Lexus has responded, that EVERYBODY was having the same issues. They have acted very uninterested in my problems, which led me to believe they had a massive problem on their hands and were just trying to keep it under wraps. If it's something about my individual vehicle, of course they need to fix it so I can get something close to expected mileage. I've told them all along I never would have said a word if I was getting 26-27 MPG, but down around 20 is just not acceptable. They treat me as though I'm a crank, despite having now bought four expensive cars from them.

gagrice

if I was getting 26-27 MPG

You are not alone. One poster from Phoenix and another from Palm Springs are getting the same 20 MPG. All of you have the same common complaint. You had a RX300 series that got about 19 MPG with normal driving. Lexus would be wise to give you your money back. It does not take many disgruntled owners to give a brand a bad reputation. I think the same thing is happening with Toyota and the Prius problems. Toyota Corporate has had a good run of reliability, and are not equipped to handle unhappy owners. Good luck and keep us posted.

rx400_owner

Short trips do hurt mileage, but even with that, you should be seeing better mileage. We have gone over 5000 miles now, including a period where we drove only short trips for two weeks. We have averaged a bit over 25 mpg (based on calculation from fuel fill-ups).

There is a TSIB about getting the idle speed training to retrain. That is a problem that can cause low mpg. I put a post with the TSIB number in the problems board of RX400 owners. So far none of the people with mileage problems have posted results of going to the dealer about that TSIB.

stevedebi

"I've told them all along I never would have said a word if I was getting 26-27 MPG, but down around 20 is just not acceptable. They treat me as though I'm a crank, despite having now bought four expensive cars from them."

Have you tried adjusting your driving habits? Try and accelerate such that you use less gasoline and more electric motors. You have to determine the best acceleration rate for your vehicle. Similarly, try and time the stoplights, and don't speed.

Heavy SUV hybrids are sensitive to changes in driving patterns, more so than smaller, lighter hybrids. If you don't want to change driving patterns, that is OK too; the hybrid has more power than the 330, and will yield better performance.

Like many people, you have fallen prey to the sales pitch (and popular notion) that you can "have it all" - unlimited lead-foot (not that I am accusing you of that, but that is the pitch) while still getting near EPA mileage. People who drive - any car - for "speed" will not get anywhere near EPA. Those who drive conservatively (and "intelligently" for their vehicle class) will achieve better mileage. To top off all of this, you are fighting a characteristic of the HSD in the Lexus - poorer MPG on shorter trips.

To put it another way, my 2003 CR-V gets 21 MPG in town when driven conservatively (19 otherwise). You have 100+ extra horsepower over my vehicle, your SUV weighs around 1000 lbs more, you have far better luxury, and yet you get better MPG than I would get driving the same way in the same short-trip circumstances.

It is a matter of perspective. I realize that this may be a different perspective than you thought you were buying with the RH, but this is the reality. If it is really bothering you, get rid of the car and save yourself the frustration. You might try talking to your dealer, emphasizing that you will be buying more Lexus vehicles in the future, and see if they will cut a deal for a 330, perhaps a demo model or something. I don't think Lexus will take the vehicle back, because it is very likely performing as designed; but the dealer wants your return business.

katzjamr

I read all i can on three major forums the good the bad and the ugly. Many of us report our mileage online and in another group with 53 people responding 75% were getting 25 mpg with thieir 400h's or better. So when you see people with results like 20 it has to be thier driving or an anomoly with the SUV. In another forum posted to day Toyota flew a hybrid expert out from atlanta to houston to deal with his particular problem. In many cases they do try to fix things they honestly want this vehicle to have a good reputation, there are many more hybrid models to come after this. To richcbt i would try to find another dealer that will verify that your 400h is within specifications, after that its your drving habits. I understand that you have been loyal to this dealer and their lack of response adds to yourdissapointment. I would also find the owner of this dealership, they can cut through alot of crap and settle this once and for all.

gunner

Thanks, The reving up is an excelleration or RPM increasing. Excelerating at a moderate pace the engine RPM'S Increase too much and the forward speed does not increase enough. Then the engine hangs at the high rpm and stays there for a while before decelerating. Also My 1997 Corvette gets 18-22 MPG average city and highway. On the open road my vette gets 28-29 MPG.????? It cost me $20k less than my Lexus. :confuse:

gunner

mirex, Thanks. My trips usually are 20 -50 miles. When I was up at Lake Tahoe the instermentation registered 33-37 MPG. where small trips around the Lake. I did get 28.75 MPG coming home in very hot weather. Once again my 1997 Chev Corvette gets 17-20 MPG in City, and 28-29 MPG at high speed on the highway.?????? I would thing your weather is cooler and more humid. This was the way it was at Lake Tahoe... :lemon:

mirex

My 400h now has 5500 miles on it. I just returned from a trip from Seattle to Portland and back. My mpg on the way down was 30.0 and the return was 29.9. I am now confident that I can consistently beat the EPA 27 mpg highway figure. I have serious doubts, however, that I will ever hit 31 mpg in city driving. I can't figure what I would have to do to get my mileage down to 20mpg.

While visiting friends I drove their 2005 RX330. Other than the wood interior, I prefer my 400h. It definitely has more power. They do not check their mpg so I do not have a comparison there. If Lexus did not make the 400h I would be happy with the 330.

richcbt

Stevedebi wrote:

"It is a matter of perspective. I realize that this may be a different perspective than you thought you were buying with the RH, but this is the reality. If it is really bothering you, get rid of the car and save yourself the frustration. You might try talking to your dealer, emphasizing that you will be buying more Lexus vehicles in the future, and see if they will cut a deal for a 330, perhaps a demo model or something. I don't think Lexus will take the vehicle back, because it is very likely performing as designed; but the dealer wants your return business."

I cannot tell you how disappointed I am with Lexus, both my local dealer and headquarters, over their bumbling method of handling my issues. Of course I want to get rid of the vehicle. I consider it to have been the worst buying disaster of my life, and it makes me angry every time I drive it.

For the record, I don't drive with an extreme leadfoot or anything remotely like that. Traffic patterns where I drive don't permit that even if I were so inclined. There is a lot of stop and go on city streets.

I took the vehicle in today and the Service Writer said he just had one yesterday that was worse--19.2 MPG. I told him about my unsatisfactory discussions with Lexus and he just shook his head.

Here's the thing, though. I CAN'T unload this car, in good conscience, without fully disclosing the lousy mileage I've been getting. So the buyer of choice, for me, is the dealer who sold me this apparently defective vehicle. Testing found nothing wrong with it, but it fails to perform up to standards that I believe I had a right to expect.

Nobody told me that it was possible I might only get the same or slightly better mileage with this $55,000 purchase, for which I paid full list like everybody else, including several dealer extras, and even got a lousy deal on my trade-in, AND have to pay up for 91 octane fuel. Sure, I like the extra power, but the NVH (Noise, Vibration, and Harshness) is way below any Lexus I've previously owned, the Levinson sound system is a pale imitation of the one I had in my 99 RX 300, and so forth. I hate the car, and have been trying to get them to make me an offer to buy it back since it had 300 miles. They haven't made any such offer, so I'm going to hit them where it hurts. I'm talking picket signs, advertisements, and even a lawsuit. It's not just me. If Lexus knows that normal drivers are getting 19-20 MPG when they are offered the possibility of 31, they have an obligation to say so to every customer in the showroom and lower expectations.

Since they won't do that, I'll help them along with it. That's all I can do

katzjamr

It is clear that you are angry with your dealer, and this anger is coloring all the feelings about your 400h. I am sure there are Lexus dealers out there who dont care, among the three in the Seattle area some are more customer oriented than others. The first words out of my salesmans mouth as we sat in the demo vehicle was 'you are not going to get 31 mpg, if u drive mosty freeway you might consider a rx330 and save some money. The demo vehicle showed 21 mpg under hard driving. My real world experience at 2400 miles with the 400h is an honest 26 to 28 mpg. We have mentioned to you that premium gas is not needed in this vehicle. In a poll at the lexusownersclub.com (usa) 55 owners responded with their gas mileage. Rich,,, LESS THAN TEN PERCENT OF THOSE OWNERS ARE GETTING 21 MPG OR LESS. More than half of them are getting above 25 mpg. Your 400h has been checked out by the dealer and looks like its up to specs. I am willing to bet that for whatever reason you are not willing to drive a hybrid in a manner that gets the best mpg. You bear some responsibility for that.

Your SUV is worth 47 to 48,000 right now, nearly new. It is quick, handles well, safe,and a great opportunity for someone to own who will appreciate it.You dont in reality have an issue with the new owner getting poor mileage because their driving route and style will be different from yours, and most likely be more open to learning the get the best mpg. Gas is 3.50 a gallon in the midwest right now because of Katrina. Many people feel we will see triple digits in a barrel of oil before the end of the year. You can sell this vehicle you hate so much with a very minimal loss, or let your anger eat you up and fight a losing battle with Lexus. There are very few suvs that hold their value after purchase as this one. Now is the time to sell it if you really want a resolution.

rx400_owner

Rich, Why do you "have to pay for 91 octane fuel?" Have you tried 87 octane in it? I've been running 87 octane and it is performing just fine. I've had it up the Grapevine into LA and it had plenty of power. I haven't had a chance to try it going over the Sierra yet - that will be the final test for us on whether there is any performance issue wiith 87. I know the manual recommends 91 for performance, but it says 87 is okay. From my experience so far, I can't imagine how 91 would improve the performance. Eventually, I will probably try a few tanks of 91 to see if we feel any difference.

Did you ask the service writer about the TSIB I mentioned. I certainly don't experience any hashness or vibration in our RX400. (Noise - certainly we get the generator whine on breaking which bothers some people. Other than that the car is reasonably quiet - not different from the 330 we test drove.)

Is there another dealer in your area? You don't have to take it to the dealer where you bought it for service. Given the difference between the experiences people seem to have with their cars, I'm wondering if some of the service techs fell asleep for part of their special Hybrid training and are setting the cars up wrong.

mirex

I tried 2 tanks of 91 octane at 5,000 miles and estimate I got a little over 1 mpg better, but I could not tell any difference in performance. I drove from Seattle to Susanville, CA. Then over Highway 50 to Lake Tahoe and on to Sacramento on 87octane. Noticeably better performance than my 2003 RX300.

I just drove round trip Seattle to Portland. 30.0 mpg down and 29.9 back on 87 octane. No complaints here on highway mileage. I am a little skeptical, however, on the 31 city estimate.

mirex

Edmunds.com has posted an article on what driving habits can increase your mpg. While the 400h was not tested, they certainly apply. Add maximizing coasting and you can probably exceed the EPA estimates for highway driving and approach the city estimate assuming you do not have numerous short drives that drastically reduce your mpg..

http://money.cnn.edmunds.com/ownership/driving/articles/106842/article.html

mirex

Edmunds.com has posted an article on what driving habits can increase your mpg. While the 400h was not tested, they certainly apply. Add maximizing coasting and you can probably exceed the EPA estimates for highway driving and approach the city estimate assuming you do not have numerous short drives that drastically reduce your mpg.

http://money.cnn.edmunds.com/ownership/driving/articles/106842/article.html

cleanair4atl

I've only had my 400h for 6 days now but I was just wondering if the battery indicator (on the dash by the speedometer) should ever read "full". It's always between 2/3 and 1/3 charged but never hits the top.

Also, has any experienced any "pull" in the steering? Is this typical of Lexus (this is my first)?

Finally, I understand that driving style has a lot to do with gas efficiency, but so far mine has been poor (20.9 mpg). I try to let the battery run the car for as long as possible, but just a little pressure on the pedal and the engine starts up. I bought this car for the luxury but mainly for the hybrid. Thanks.

75cavalier

I have the same thing with my battery indicator. I can never get that final green bar, no matter how far downhill I drive. Waiting to take it back to the dealer for 5K miles to inquire. It also seems to drain rather quickly, even when the engine is turning.

I have the pull in steering, too. Took it back to the dealer who re-spec'd the front end, and even checked tire balance. It still does it, but not nearly as badly as before. My first Lexus, too, so I can't offer anything beyond that.

I average 21-22 around town. Not what I expected, especially since every other car I've owned I've beaten the EPA estimates. Still, it's almost double the Trailblazer I traded, and it's low emission, so I feel like I'm helping the environment.

I do wish they'd used the wood trim from the RX 330, though.

katzjamr

I have 2500 miles on my 400h, as far as i know you will never see that last bar. It will turn green when it is at the second bar from the top and start to slow the amount the battery is charged. Normal is from two bars to one from the top. Regarding pulling the 400h is mostly front wheel drive a majority of the time and this suv has more torque steer than other cars especially under harder acceleration. That being said the vehicle should track straight on level ground. This steering also seems to be more sensitive to crowns in the road, and want to pull as a result of that. If the car does not track straight under what you think are normal conditions i would insist that the dealer balance the tires, and align the front end. This has cured most issues with steering. I will repeat it again, for some reason Lexus has been sending out alot of 40hh with tires inflated to 40 psi. That was the case with mine, i took a tire gauge when i picked up the suv and fixed it at the dealer. You would think dealer prep would catch this. Regardless, improper tire pressure is another cause of steering problems, and easy to fix. I urge everyone to check this first, depending on the tires you have it should be 30 or 32 psi.

maxamigo

I've seen the "last bar" on my Prius once. I had it in "B" gear when coming down Acadia Nat'l Park's mountain. It was only about 3k ft mountain but it had quite a charge.

rlevering

After 3700 miles of in-town driving, my 400h has not exceeded 25 miles per gallon. As I have relaxed my driving habits during the past 300 miles, average miles per gallon are declining to 22-23. Unlike the favorable mileage experience reported by the Seattle observer, my Lexus Dealer's service rep reports widespread disappointment among early buyers with mileage perfromance no better than mine. When offered the opportunity to evaluate the settings on my 400h, the service rep showed no interest in doing so. Why should any prudent buyer pay $10,000 more for little or no mileage improvement, very marginal acceleration improvement and very complex engineering? I fear Toyotal Motor Corp is using we early adopters as guinea pigs for their second and third generations. If so, we early adopters pay the price twice, first in mileage performance and second, in accelerated depreciation made even worse when second and third generations are introduced. I also sought resolution with Lexus Corporate in Southern California and was treated only with SCHMOOZE and NO SOLUTIONS. I can only hope that some widespread uprising among disappointed buyers will lead Lexus to a total recall or reimbursement of all consumers who believed the advance billings and laid out the $53,000. Rex

rx400hfan

I am very happy with the mileage I have been getting with my RX400h. I have been seeing significant gains on each tank. My manually calculated mileage per tank have been 25.9, 26.2 and most recently 28.8. This is with a daily work commute of about 8 minutes each way. It is very evident on the consumption display that the first 5 min. mileage takes a considerable hit to warm up the engine. Having had only 3 work day commutes and several 30 to 40 min. drives on my current tank my consumption display stands at 31.7 mpg with 305 miles driven and the gas gauge needle just touching the bottom of the half tank mark! This tank has included a lot of 40 to 50 mph driving but has included about 30 min. of 65 mph several 500 ft. elevation changes as well as hitting 80 mph passing several vehicles.

katzjamr

I think you are correct in stating that some early buyers must have voiced some disappointment with mileage. When I test drove one in June my dealer had only 400h trained salesmen sell the hybrid cars. As i have said before, the first thing he said to me was you are not going to get 31 mpg its gonna be around 25 and Lexus wants u to know that. It kind of took me by surprise but i appreciated his honesty, and it made me check out the rx 330 more closely. Sure the 330 was cheaper but after i drove it i felt the 400h handled better, there is a pronounced quickness at all driving speeds in the hybrid and i think it looks better. I think Toyota made a conscious decision to value power and options over fuel economy with this model. The hybrid Camry and another truck will be out soon. Its my feeling that those brands will skew more to fuel efficiency. Also most likely fuel is going to remain high and at 3.00 a gallon or more which will shorten the payback time.

maxamigo

My mixed driving gas mileage has gone up to 28.6mpg last 200miles (from ~26mpg) after I changed oil to Mobil-1 synthetic gold cap. I made the same change in my wife's Prius and it went from ~52mpg to ~62mpg in city.

This is not to say that you'd get the same number because your driving style is probably different from mine. Some people I've seen would plow pass others just to stop first at the red light, then jump out by car lengths when the light turns green. That kind of driving just isn't going to get good mpg on a hybrid. If that's the way most people drive, then most people will be disappointed with their 400h gas mileage.

Secondly, the way EPA defines "City" MPG is likely not the definition of city you have in mind. I am pretty sure if I cruise on country road at 30-35mph with minimal braking, I would get 31+ mpg assuming good autumn weather. In a regular vehicle, the difference between EPA definition and yours may not be all that apparent. But in a hybrid, that difference is far more obvious. I think it's key to find out HOW they evaluate a vehicle for "city" mpg.

katzjamr

I had an early oil change at 1500 miles and my dealer says they use Castrol syntec blend oil. Your results with the Mobil One are very interesting, especially since you have improved your mpg in two vehicles. How many miles were on the suv when u switched, and do you think its reduced friction that improves the mileage? or???

surwit

My last post I was complaining that my mileage was only about 19-20 mpg. Lexus checked it several times and concluded it was working according to spec. All of a sudden, I now have 4200 miles on the car and my mileage is starting to improve. I got 27 mpg on a 200 mile trip at highway speeds (65-70). While I still rarely get more than 20 mpg during the first five minutes of any trip (even when the engine is warn), I am starting to routinely see 30+ mpg after that. Still, the grade influences mileage considerably, so on uphill segments my mileage is not as good as on flat ones.

I'm not sure what was responsible for the change. Break-in, somewhat cooler temps? None the less, I am now quite happy with the car. It is quiet, powerful and fast, and the mileage is definately better than my old RX 300. With the price of gas over $3/gallon, I am very satisfied with this vehicle.

lexrexblue

Sounds like good news. It'll be awhile before I reach that mileage. Are you using regular or premium or the middle grade of gas? I'm curious after the Lexus suggestions. I was thinking of consulting the dealer and see what they really suggest.

mirex

The following are the calculated figures for my 400h delivered on 6/3/05

Total Miles Driven = 7080
Gallons Used = 262.168
Total Cost = $691.41
MPG = 27.006
Average Price /Gallon = $2.61

Estimated 90% highway and 10% city.
Includes one round trip Seattle to Lake Tahoe and five round trips Seattle to Portland.
I use cruise control (set at posted speed limit) whenever it is safe to do so and the A/C is generally set at 74 degrees.
Four tanks of premium, the balance 87 octane. About a 1/2 mpg increase with the premium. I always use major brands such as Chevron, Shell, and Union 76. No Safeway or Costco.
I rarely punch the accelerator and coast when I see a red light in front of me.

Observations:
I am now averaging 29+ mpg on trips to Portland.
The calculated mpg is about 1 mpg less that what the navigation screen shows.
The city driving actually lowers my average mpg.
Extended stop and go traffic causes the battery indicator to change to lavender which causes the ICE to run in order to charge the battery.
Short trips before the ICE warms up average about 22 mpg per the navigation screen.
My average mpg did show an increase after 5000 miles.
I am averaging about 5-6 mpg better than on my 2003 RX-300.

maxamigo

That was at ~5k miles when I made that change. Since then, we've taken a long trip to the northeast, into more mountainous terrain. here's what I found:

On the trip from FL to Washington. 90-95F. We got 24.5mpg trying to keep up with traffic.

When NH, VT, NY regions, we got 29mpg in hwy, but we had to learn how to take advantage of downhills (White mountain region) and how to coast with it. In Montreal's heavy trafic, we got as high as 29.8mpg (learn how to move with trafic with least of braking) and that was for about 280miles stretch before we had to go hwy. The temperature was 75-80F during this period, low humidity.

Then we got 28mpg coming back to FL.

What we had: 3 passengers with medium amount of luggages and this was rather constant through the whole trip, Mobil-1 synthetic gold cap, stayed at 87gas.

maxamigo

We're at past 8k miles now.

IMHO, the factors involved in gas mileage improvements are:
1. engine+hybrid system broke past the new period.
2. mobil-1 new synthetic gold cap
3. less demand on AC system in cooler weather.
4. I got better in learning how to drive a 4k lbs vehicle and when to coast for best result.

Also, as a rule of thumb, I change oil when it turns to darker brown, not when certain miles had passed. The color of oil indicates how much of the oil polymer chain molecules had broken down (called "cracking" in petro-engineering term). Broken chain means less lubrication capability.

katzjamr

Thanks keep posting your results. I am at 3500 miles, had one oil change with the castrol synth blend my dealer uses. I swore i would never do it but i used premium fuel the last two fill ups and did increase mpg from 25 to 27 mixed driving to 27/29 mixed driving. The ICE seems to kick in more abruptly with premium fuel, something another poster verified for me in their 400h. Been happy so far, waiting for that breakin period on the hybrid system to be done. Would like to take a trip but its been busy at at work. thanks

lparadis

I have owned my 440h since May 2005. The car is beautiful, but it certainly is getting lousy gas mileage in comparison to what would be expected!!!!!!!!!!!!!!! I have never had a tank average over 22.5 since the day I bought it, and I drive an average amount on average roads at average speeds with average air-conditioning etc etc. I spoke to a Lexus customer service person who said his experience in a a drive of about 500 miles was between 21 and 23 average. That sure is a far cry from 28-32!! At 5000 miles, I still get 22 mpg

maxamigo

Driving styles make a lot of difference in Hybrid vehicles.

I can get 22mpg easily with more aggressive driving and more abrupt stops. But if i tone it down, the mpg gets a lot better.

Check other posts for driving tips...

lexrexblue

How did you resolve the squealing brakes? Mine are squealing out of the garage. It is embarrassing in the morning because it pierces the silence on the street! It only happens when I back out of my garage.

dahlia555

I just picked up my 400h three days ago and haven't filled up the gas tank yet. My salesman told me to ignore Lexus' premium gas recommendation. He said that he went to a training where all of the salespeople were told that the Rx400h and Rx300 run better and more efficiently on regular gas. Has anyone else heard this? What type of gas are you using? Have you tried regular?

mirex

I have 7700 miles on my RX400h and am averaging 27.06 mpg. I noticed a slight increase in mileage after 5000 miles. My last two round trips from Seattle to Portland have averaged 30.0 mpg.

I did run a couple of tanks of premium and I estimate a little over 1 mpg improvement, but did not notice any difference in performance.

Last night I attended a Lexus service clinic at my Lexus dealer. I asked about using synthetic oil. My dealer uses Castor Oil products. They have not used synthetic oil in any of their customer's 400hs. but think there could be a 1-2 mpg improvement due to less friction. I think they said that the synthetic oil costs almost triple, however.

So theoretically, you might see a 3-4 mpg improvement with premium fuel and synthetic oil. I haven't run the figures, but I don't think the numbers pencil.

candido

I have about 3500 miles on my 400h which I got in August. I have consistently been averaging around 30 mpg. On a 300 mile trip, I went about 75mph on the way there and got about 26 mpg. On the return trip, I went no more than 60-65 mph and got 30.8 mpg. Last week I went on a 35 mile trip during rush hour in Chicago and got 31.1mpg as an average.

People who make a lot of short trips of 5 or 10 minutes are likely to have worse mileage. In my car the mileage tends to decline a tenth or two every time I have to start the car. Now I tend to park the car and walk around town or the strip mall instead of driving around from one end of the parking lot to another. Right now I am experimenting with different grades of gas.

I couldn't be happier with the car. I had a 300ES before this one. I was happy with it, but the 400h is just about ideal for me. I would say that the only complaint is the camera on the back seems to distort, but this is a very minor item. If I had had the choice, I wouldn't have gotten the navigation system, but I find it very useful and am happy to have it. I didn't get the car to save money; I got it to save gas.

bainse

What the heck?? With all respect, this seems kind of unbelievable. And I don't know what BMW vehicle you're talking about having the "same gas mileage" and "faster acceleration" ... certainly not any of the BMW SUVs. While this forum (and Lexus) can benefit from healthy criticisms, I have to wonder whether you really are a 400h owner, or a competing dealer or something!

maxamigo

Excellent!

I took a picture of the dash monitor showing 31mpg for the last 1200+miles. The car now has almost 10,000miles. Is there a place to post the picture?

nigh

My 400h has a little over 5000 miles on it right now. I drove from Annapolis to home (about 25miles) last week with no a/c on and got an average of 30 m/gal. Impressive, but on an average I get around 25/26.

loosegoose

We have had our Lexus400rh since May and apart from a trip to Colorado where we got pretty good mileage 22-23 on the back country driving and fantastic power and mileage in the mountains, our mpg has been in the 19-20 mpg range. On discussing this with my Lexus salesman his reply was I must be 'too heavy on the pedal."
Since this remark, I have paid a LOT of attention to how I drive. I feel like a little old lady and constantly have unhappy drivers behind me. Finally my mileage is a little better 20-21mpg but only because I am not using the A/C now.
A neighbour who was thinking about buying a 400h asked how I liked my car. I told her I was very disappointed in the mileagebut otherwise I loved it. She bought one and guess what. It was a demo model with 900 miles in it and she gets 28 mpg driving the same terrain. I quizzed her about her driving and it seems our methods are similar so I am stumped.
It is no fun driving a car when you are constantly working on improving your mileage!

katzjamr

It might be easier to go for a drive with her if that is possible. She may be doing some things you are not aware of, or infact gets less than 28mpg consistently. If she is using premium fuel that will account for a 2 to 3 mpg improvement. If your trips tend to be shorter that will make a huge difference, any trip in this vehicle that is just a few miles from a cold start is a mpg killer. Learning to drive in a way that maximizes mpg can be fun once you learn how.

loosegoose

She is using reg gas AND the A/C. I am using reg and not the A/C since it is cooler now.
We are going to get together and try each others cars out.

mirex

I have found that the mileage reported by the navigation system is not accurate and the best way to know your true mpg is by dividing the number of miles driven by the number of gallons used. I have used this method since I received my 400h on 6/3/05. After 8800 miles my average mpg is 26.926 on regular gas.

On recent trips between Portland and Seattle I am getting 30.0 mpg. My city/highway driving includes several short trips which pulls my average down to 26+.