Mpg

[SOMEONE ELSE'S GOT MY NAME]

I live in Denver so perhaps we are blessed with the higher altitude but with about 3000 miles on my 2007 400h I am averaging about 28 MPG on 85 octane. I have tried 91 octane a few times but did not see any difference in MPG or performance.

Is the mpg calc's off your MFD? . . . or actual number crunching.

[rjs]

The MFD shows 27.9 but I also check the actual fuel usage which tends to vary from the MFD. Last time filled up I had traveled 417 miles and used 14.8 gallons which averages about 28.2.

As for the temperature here in Denver the highs have been in the 80s and 90s since I bought the car.

[RolandB]

I have approximately 31,000 miles on our 2006 RX400h with a lifetime average of 22.56 mpg! I re-experienced an unexplainable occurrence. Without a lot of elaboration, I have taken the car to the Denver area each of the past two summers and I experienced approximately 3 mpg better gas mileage in the mountains than the flatlands of Texas. I am totally bewildered. I consulted with Denver and Dallas service personnel about 'tweaking' the carburetors like we did in yesteryears for 'mountain' driving. Is there a reverse that's applicable to the 2006 RX400h?? I would have guessed the mountains would be tougher and more glutonous. I keep very accurate records. Yes, I had to use a different gasoline but only because 'mountain regular' was less than the 87 octane we have here in Dallas.

Any comments/suggestions appreciated.

So what octane are you using in the mountains? 91 at 5300 ft. is like 93 in the flatlands...perhaps you get more mileage because of higher effective octane at altitude. What do you tend to drive when in CO? Short trips around town or highway miles?

I was unaware that one didn't need the higher octane in the mountains. I was always using one equal to or greater than the Regular grade we have here in Dallas which is 87 octane! My driving was a mixture but predominately highway! Here, the driving is predominately in-town type! I tried using a higher octane here in Dallas some time back and did not discern any significant improvement. Premium grade gasoline here is about 10% more in price ($0.25) per gallon! I don't mind spending if I get an equivalent improvement in price performance!

[RolandB]

I live in Denver so perhaps we are blessed with the higher altitude but with about 3000 miles on my 2007 400h I am averaging about 28 MPG on 85 octane. I have tried 91 octane a few times but did not see any difference in MPG or performance.

I will assume that's a 'calculated' MPG rating vs the 'indicated'.. (the indicated is per my calculations always more than actual). I should now look to other factors such as A/C. In Dallas, we will be running the A/C almost always. In Colorado, I know the ambient temperature was much less than the Dallas ambient temperature! Especially, the morning temperatures and after sunset are much cooler! Maybe there's the culprit. An electric A/C compressor will draw on the battery which must be recharged by the engine or downhill coasting! I am still mystified by the noticeable difference!

[Gryphon]

I have a limited mpg report:

flat terrain, premium fuel, steady speed of 85 mph on cruise control, moderate cross wind -

19.0 to 19.5 mpg

This was the displayed mpg, not calculated, and over about 50 miles

Not impressive considering that most vehicles traveling along the same road were probably doing better.

Tom

[JMR]

I've had my 2007 RX 400h for 1 week and just filled-up for the first time today. I had 24.6 mpg on the first tank, but that appears to have included some "contributed" miles from the dealer (test drives?) that were on the low side. The rate was going up throughout the week. I'm looking forward to this tank's MPG.

I filled-up with Wawa-92 octane.

-Jim.

[3sticks]

I bought my rx400h Jan 1st. Sticker claimed 27-35 mpg. After 2500 miles (I drive a lot) I am getting about 24 mpg.

Anyone getting more?

[3sticks]

got my RX 400h last Dec, 5500 miles and average is 23.7 mpg, 30 % is to & from station and around town, balance is highway at 65-70 mph. still much better than the RX 330 and we feel we are doing something "green"

[Toups]

538 miles, just purchased, not broken in with gentle-moderate driving 40% city 60%hwy

24.5 mpg

[RJChybrid]

Nearing 30,000 miles on an '06 RX400h. Tire pressure set at 32 psi. I use Cruise Control as much as possible (my dealer said this would get the best mileage) even in town @ 35 mph. I never use the "B" for engine braking, the regeneration function of the braking system means I slow down, I charge the batts and the mechanical brakes don't wear out, so why use the "B"? I use alternate tanks of 93 then 89. I drive the speed limit, what ever it is. Here's what I've experienced:

The ICE is ocassionally rough on startup, but it's a quirk I can live with. I can pass and merge at will and I LOVE this power and instant torque. I have found that transmission shifts are annoying in my wife's SC430. I have averaged 29.3 over the life of the car (according to the computer). I get better mileage than I expected, better power than I expected and my Lexus dealer is superb. I know that others haven't gotten the mileage that I have and I'm sure the explaination is that it is HARD to not use all that wonderful, buttery smooth, instantaneous torque AND get good mileage. If you save the power for the rare ocassions when it's needed and use the cruise control (let the computer figure all that stuff out) and operate at the speed limit (no "grandpa" driving), use the correct grade of fuel (read your owner's manual), there is no reason not to get similar results.

This is an amazing car that comes close to letting you have it all - greeness - economy - power - luxury. What's not to like?

[SOMEONE ELSE'S GOT MY NAME]

Nearing 30,000 miles on an '06 RX400h. Tire pressure set at 32 psi. I . . . .

snip

This is an amazing car that comes close to letting you have it all - greeness - economy - power - luxury. What's not to like?

You'e doing great on the mpg there. If you don't mind the slight difference in the ride, try bumping your tire pressure up 4~5 lbs. It'll really help the mpg go higher, and it's still w/in the tire manufacturer's recommendations.

[RXREY]

RX400h owner...I started with about 26 and now I can only get about 24. This last tank I got 25.4(387 miles/15.2 gallons) but I was on longer trips(40 miles one way...I don't drive much so I realize "long" trip is relative...in two years I have 19K miles...) and that usually helps me in L.A where there's lots of traffic, we tend to drive long and slow for many miles and I can watch the mileage go up,up,up since I am in basically a luxury golf cart at that point.... But realistically, when I drive in a more fun manner...I get about 24. I too am not pleased at how the salesman was sure to tell me when I bought the car that I would get over 30...but even Lexus salesman have to lie...it's a DNA thing and we can't be too harsh...many of them can't even afford the cars they sell! I also have to mention that I believe I might have lost 1mpg with the TOYO Proxes 255/55 tires(they're a little bigger/heavier...but far superior to the OEMs) I love my "Princess" though, this has been the best car that I've ever had. Rey in L.A.

[packman]

We have an '06 400H, Idrove it for the first 10,000 miles averaged 19-21 mpg. Gave it to my wife she is averageing 29 mpg....all in town driving

[mindmachine]

RX400h owner...I started with about 26 and now I can only get about 24. This last tank I got 25.4(387 miles/15.2 gallons) but I was on longer trips(40 miles one way...I don't drive much so I realize "long" trip is relative...in two years I have 19K miles...) and that usually helps me in L.A where there's lots of traffic, we tend to drive long and slow for many miles and I can watch the mileage go up,up,up since I am in basically a luxury golf cart at that point.... But realistically, when I drive in a more fun manner...I get about 24. I too am not pleased at how the salesman was sure to tell me when I bought the car that I would get over 30...but even Lexus salesman have to lie...it's a DNA thing and we can't be too harsh...many of them can't even afford the cars they sell! I also have to mention that I believe I might have lost 1mpg with the TOYO Proxes 255/55 tires(they're a little bigger/heavier...but far superior to the OEMs) I love my "Princess" though, this has been the best car that I've ever had. Rey in L.A.

You are loosing MPG because your larger diameter tires are aproximately 3.6% larger in diameter and therefore your odometer is registering less miles than you are actually covering. so your 25.4 mpg you got recently should be mutiplied by 1.036 and you actually got 26.31 MPG.

Typically 255/55 tires are 29 or even 29.1 inches in diameter and the recommended tire size is 235/55 is 28.2 inches in dia. so the larger diameter tire goes less revolutions to cover the same distance and hence you are driving 1.036 x 387 miles or 401 miles actually when your odometer read 387 miles.

Also because they are bigger/wider they probably have more rolling resistance and hence may lower your gas mileage. With the correct tires you probably could get at least 27 MPG or better based on your report of 25.4 mpg with your current set up.

:chairshot:

[RXREY]

Actually, thanks to the wonderful and brilliant Lexers on this site I have been multiplying my total mileage by .03...to compensate for the larger circumference of my Toyo tires, so I am really getting the 25.4...all factored in for your edification. I love this site. Thanks again, Rey

[Colo Springs RX400h]

We have gotten an average of 27.4 on our 2006 400h over almost 15,000 miles. I track it on greenhybrid.com. The overall average on the site for 48 400h's is 25.4.

I get 28.6 to 29.1 in the Summers. In the Winter I only get 25.8 to 26.3.

[RXREY]

This last tank was the best in the two years...450.1 miles on 16.6 galllons....= 27.1 MPG. Rey in L.A.