gotin

AWD.
As far as I know FWD is not available in Europe.

bring

Thanks - just wanted to confirm we were talking apples to apples.

Aptosuser

My standard of comparison is the '07 six-cylinder RAV4 that I drove before buying my Lexus. I consistently got 27 mpg or better when driving it on our freeways at 60-65 mph using cruise control wherever the road was not congested.
The best I could do in my RAV4, in what passes for city driving around our house -- the up-and-down, two-mile drive between our house and our health club, including five all-way stop signs, where I always come to a full stop -- was about 18 mpg. My bluetooth Garmin GPS received engine data from a transmitter plugged into the car's OBDII port. I found that I could maximize mileage along this route by using the pulse and glide method while I kept an eye on the Garmin's virtual engine-load gauge. The lower I could keep the load as I drove, the better mileage I got.
I'm getting about the same highway mileage in the Lexus that I got in the RAV4.
What do you mean by "motorway driving"? Going 100 mph on an autobahn? Most places in California the top speed limit is 65 mph, dropping to 55 or 50 in heavily urbanized areas. I always observe the speed limits, unlike most other drivers around me. I just try to stay out of their way.

That is certainly true, as it is for pure ICE vehicles as well. On our local stretch of freeway, where the longest trip I take is only nine miles, and the speed limit is 65, I routinely stick to the right-hand, "slow" lane at 60 mph, except when either passing even slower cars or making way for merging traffic, when I change to the left-hand lane and accelerate to 65 so as not to become a "road boulder."
That's for sure how the HSD works in our 2012 Camry hybrid. But I haven't been able to duplicate that in our RX hybrid. I'm hoping driving in snow mode -- which I agree should be renamed eco-plus -- will change that.
Again, so far I've gotten much better mileage on extended freeway trips at 60-65 mph, sometimes hitting 30 mpg. It's these trips that have kept the RX hybrid's average mpg at 27.2 since I bought the car in mid-November. I often shake my head when I see other Lexus hybrid drivers zooming past me at 70-80 mph. I know that they are only defeating the purpose of paying the "hybrid premium" for their cars in the first place.

Finally, this is one of the most interesting and useful forum discussions in which I've participated. Thanks to everyone, and especially gotin, for a fascinating exchange!

gotin

I could be wrong in the precise meaning of highway and motorway but in Europe we have three main speed limits and I suppose it is similar in the USA.
50 km/h (~30 mph) - city driving.
90 km/h (~55 mph) - highway (outside the city) driving.
130 km/h (~80 mph) - motorway (Autobahn in German) driving.

In the vehicle specifications we always find fuel consumption data only for the first two types of driving. The fuel consumption specifications are too obsolete, because today most of the driving, at least between big cities in Europe, is on motorways. Long trips on motorways usually build the biggest mileage.

My mileage so far is roughly divided in three parts:
~1800 km (~1110 miles) - city driving.
~1000 km (~620 miles) - highway (outside the city) driving.
~6000 km - (~3730 miles) - motorway driving.

This is pretty normal ratio between the three main types of driving. My decision for buying a new vehicle could be based on the available fuel consumption data ONLY for 30% of my driving, if fuel efficiency is very important for me.

gotin

If we want our complaint about poor fuel efficiency of RX450h to be solid and meaningful we should compare very similar or identical vehicles.
It is fair to compare RX450h with RX450h by different circumstances. For example a fair question would be:
I achieve pretty close results on highways and super disappointing results by city driving. What is wrong with the RX450h official city fuel consumption?
It is also fair to compare RX450h to other Lexus hybrids. For example:
RX400h is achieving 10% worse results by city driving than the official data. Gs450h is achieving 10% worse results by city driving than the official data.
Why RX450h is achieving 30% worse results by city driving than the official data and all other Lexus hybrids achieve reasonable results? What is wrong with the RX450h official city fuel consumption?

dxr

by consumption data do you mean the epa estimate or what the computer displays as the mpg? in either case, I'm getting 28.5avg mpg which is about 0.3 off of my calculations and is about on the money with epa estimates

Aptosuser

I just returned from my daily 4-mile round trip to our health club. Overall it's downhill going and uphill returning (there's about a 250-ft. elevation difference) with previously mentioned, intervening dips and rises. I drove in snow mode both ways today. My downhill mileage, where I can do more coasting was disappointing; still only 19 mpg by the car's computer. But I gained mileage on the return, hitting 19.9 average mpg for the trip when I pulled into our driveway. According to the NAV energy-monitor screen, snow mode does keep the car on battery power more and on combined battery and gas power other times, using both the front and rear electric motors. But this doesn't seem to help much on the downhill leg. Any ideas on that?

After 3,352 miles since I bought this car (I started with 14,992 on the odometer in mid-November), I am doing better than the EPA estimate for highway mileage and haven't come anywhere near the 30 mpg estimate for city mileage. I ascribe this mostly to the terrain here which not flat. Per Fuelly, my average mileage overall now stands at 27.2. I am pretty happy with this, as I bought this car as much for its comfort, ride and power when I need it. If I were truly mpg-obsessed, I would've bought a Prius v.

gotin

Average or combined consumption is only defined in EPA Fuel Economy Estimates and it is calculated using a weighting of 43% / 57% city/highway, respectively. Average has no meaning in real life unless your driving is also divided 43% / 57% city/highway.

Let's suppose that I will clear my consumption data on 1 of March and in the end of the month I will know my average monthly fuel consumption.
Case 1: If I stay the whole month in the city and my city mileage is 500, then my monthly average fuel consumption will be 27 mpg for 500 miles, according to my current results.
Case 2: Lets suppose now, that I made also two family vacations, additionally to the 500 miles city driving and my highway mileage is also 500 with highway fuel consumption 31 mpg. In such a case my monthly fuel consumption will be 29 mpg for 1000 miles.
Case 3: Lets suppose, that I travelled to a ski resort 500 miles away, which results in 1000 miles high speed motorway driving with fuel consumption 21 mpg. Together with the 500 city driving miles I will get a monthly fuel consumption of 23 mpg for 1500 miles.

I am trying to explain that average fuel consumption can vary greatly depending on your driving conditions and there is absolutely no point to discuss and compare it unless we gain the same mileage by the same conditions. It is only meaningful to share and discuss the two official fuel consumption numbers which are 30/28 mpg city/highway for RX450h AWD. Most people have problem to achieve good results by city driving and this is what I meant in my previous post.

I find it very useful to discuss our fuel consumption but we must be "talking apples to apples", as bring mentioned.

Aptosuser

A good way to compare the mileage you're getting with other Lexus drivers' performance is to go to Fuelly.com If you click on the link, it'll take you to a page with all the RX 450h vehicles registered on the site. Everybody calculates their mileage the old-fashioned way, dividing miles traveled since the last fill-up (or "Fuel-up") by the number of gallons it takes to fill the tank again. The most data available is for 2010 RX hybrids, with 12 vehicles (out of a total 22 cars for model years '10-'13) and 379 fill-ups over more than 99,000 miles. These 12 RX hybrids are currently averaging just over 26 mpg overall. The highest recorded mpg in this group is 29.7, over 19,726 miles in reported 50/50 city/highway driving. The lowest is 19.9 over the course of 3,300 miles and 14 fill-ups with 74/26 percent city/highway, respectively. The latter Lexus owner lives in Canada and registered his car with Fuelly in October, so his recorded mileage has mostly been during very cold weather, which would certainly sap his mpg.

sunnyside

I am confused. I just saw posts talking about snow mode. I have a 2013 450H FWD. If there is a snow mode somewhere in the 6 inches of the manual, I haven't found it! Mileage around ATL is 28-29. No complaints here,

Aptosuser

I don't think there is a snow mode in front-wheel-drive-only 450h's because it relies on a rear electric motor that can power the rear axle. I am still experimenting with it and not sure how much it will help in our area, where the streets are not flat. It seems to make a difference going uphill, but not much when the going is mostly downhill.

Mors

Try the following link: http://drivers.lexus.com/t3Portal/do.../sec_02-01.pdf

■Selecting snow mode
Use snow mode for accelerating and driving on slippery road surfaces such as snow.

1. Press the menu switch.
   The multi-information display will change modes to electronic features control mode.
2. Press the “∧” or “∨” switch until “ECT SNOW” appears.
3. Press the “ENTER” switch to change to “ON”. The “ECT SNOW” indicator will be displayed. Each pressing of the switch turns snow mode on and off.
4. Press the menu switch to change to the normal display

Aptosuser

"ECT Snow"? What's the ECT stand for? In our car it comes up "hybrid snow." So it's available in front-wheel drive cars? How does that work?

In any event, I'm dubious about whether snow mode actually results in increased mpg. I tried it again this morning and if anything, mileage along my every-day route to the fitness club was worse in snow mode than the day before when I did not drive there in snow mode. I was mostly going downhill and either running on the battery or charging it, per the NAV "energy monitor" screen. The ICE was not running for most of the way, and still I didn't see any gain in gas mileage. Later, when I was driving on a mostly flat road and the car was again running on the battery, not the ICE, my mileage was not ticking up steadily the way it has on the same stretch of road without snow mode engaged. So I turned it off and watched the mpg start to rise. As snow mode seems to keep the car running like an EV more of time this seems counter-intuitive, but there it is. Any ideas about this, anyone?

gotin

I will start with the LEXUS classification for:
1. MICRO HYBRID ... When the car comes to a halt, the petrol/diesel engine is shut down (at traffic lights, for example) and restarts only when the driver activates the accelerator.
2. MILD HYBRID … A parallel mild hybrid uses the same ‘Stop-Start’ system as a micro hybrid plus it uses the electric motor to supplement the engine during acceleration.
3. FULL HYBRID …The most sophisticated of all hybrid systems - and the one used in our cars - full hybrid cars can be powered by just the electric motor, the combustion engine or by both.

1. RX450h starts to perform as a MICRO HYBRID immediately after warm up. The gasoline ICE is shut off when you lift your foot from the gas pedal. When the ICE is shut off - you save fuel. Snow mode has no effect on this type of fuel savings.
2. RX450h starts to perform as MILD HYBRID immediately after start and the use of the electric motors together with the gasoline ICE saves you fuel. Snow mode has no or negligible effect on this type of fuel savings.
3. RX450h starts to perform as a FULL HYBRID after warm up. Driving by electric motors only saves you fuel. It occurs by gentle pressing the pedal when the gasoline ICE is shut off. When you achieve to drive the car only by the electric motors, you save fuel.

How stuff works:
1. You press the gas pedal.
2. This action is transformed by the gas pedal sensor in degrees (rotation).
3. These degrees are transformed into power demand and anticipated reaction of the vehicle.
4. The computer distributes this demanded power between the electric motors and the ICE, according to his internal algorithms. If the demanded power is small enough, the computer tries to use the electric motors only. If the anticipated action is fullfilled by the electric motors only, you save fuel!
5. When the computer can not achieve the anticipated action with the electric motors only, it starts the gasoline ICE and your hybrid fuel efficiency is reduced greatly to MILD HYBRID performance only.

If you want to achieve maximum fuel efficiency you must drive the car in such a way that you maximize the time when the car uses the electric motors only. For simplicity and easier understanding we will accept that if you press the gas pedal up to 15°, depending on the current speed and the road inclination you will succeed to drive in extended electric mode only. As described in my earlier posts, Snow mode changes the computer behavior and as a result, if you press the gas pedal up to 20°-25°, depending on the current speed and road inclination you will achieve to drive in extended electric mode only. In snow mode RX450h uses more the rear electric motor as described by Aptosuser. I might not be correct in the exact degrees (only Lexus software engineers know them) but I believe, this is how Snow mode is helping you to save fuel - by giving you more freedom, by making the gas pedal more forgiving, by using different power distribution algorithm. Of course this comes with slower acceleration.
If the traffic in your city is forcing you always to accelerate rapidly, if you do not stop so often, if you can not achieve keeping certain speed with electric motors only, then you will hardly notice the benefits of Snow mode. Your city fuel consumption will be disappointing, because you are not benefitting from the FULL HYBRID algorithms, implemented in your RX450h.
If you drive like me in the center of a European city with maximum speed 30-40 miles, you will get noticeable reduction in your fuel consumption when using "Snow mode", at least I do so far.

One final advice, if the traffic allows you. When your RX450h is stopped at the traffic lights and you must start - lift your foot from the brake and wait a fraction of a second, until the car starts to move and then press gently the gas pedal. When the car is already moving, no matter how slow, it is much easier to drive in extended electric mode. If you want to play more, reread the excellent post of Three60guy and activate the EV mode. Starting by electric motors only is easiest n EV mode.

Aptosuser

I will give EV mode another try the next time I drive. As I've said before, I've never been successful in activating it. I've always gotten a message saying that it's "not available." I'll try it at a stoplight after the car is warmed up and see what happens.