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I have previously owned an RX400h for four years and was getting close to the combined economy figures regularly, namely 32 to 33 mpg against published figures of 34.9 mpg. Admittedly thus was only achieved by not pushing the car hard and mainly driving on country roads with some town driving and very little motorway driving.

I am now driving an RX450h, which has only 4500 miles on the clock, but I find it very difficult to match what I was getting from my RX400h, even though the 450h should return about 10 mpg better for combined driving. I am driving in the same manner on the same roads as I had been with my 400h, but I'm consistantly getting only 29 to 30 mpg.

I have been around long enough to realise that manufacturers published figures are always over optimistic, but I was consistently getting within a few percentage points of the RX400h combined figures,whereas I'm not getting better than two thirds of the published combined economy figures for the RX450h.

Are there any other RX450h owners out there who are getting anywhere close to the published economy figures, or are they close to complete fiction?

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I have previously owned an RX400h for four years and was getting close to the combined economy figures regularly, namely 32 to 33 mpg against published figures of 34.9 mpg. Admittedly thus was only achieved by not pushing the car hard and mainly driving on country roads with some town driving and very little motorway driving.

I am now driving an RX450h, which has only 4500 miles on the clock, but I find it very difficult to match what I was getting from my RX400h, even though the 450h should return about 10 mpg better for combined driving. I am driving in the same manner on the same roads as I had been with my 400h, but I'm consistantly getting only 29 to 30 mpg.

I have been around long enough to realise that manufacturers published figures are always over optimistic, but I was consistently getting within a few percentage points of the RX400h combined figures,whereas I'm not getting better than two thirds of the published combined economy figures for the RX450h.

Are there any other RX450h owners out there who are getting anywhere close to the published economy figures, or are they close to complete fiction?

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I have RX450h SEL - one month old and currently getting 31.3mpg. Best I have acheived on any journey is 36mpg - but only for part of the journey.

I have today started process of complaint and asked dealer to explain/test car. I am asking for them to take me on a run - I will pay for the fuel and demonstrate getting even 36mpg+ on a motorway drive.

Fuel consumption was a big influence on my purchase decision and 27% below published figures is unacceptable and I believe illegal under trades decription act.

Would really like to collect data from all owners on what they actuall get!

Cheers

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I have RX450h SEL - one month old and currently getting 31.3mpg. Best I have acheived on any journey is 36mpg - but only for part of the journey.

I have today started process of complaint and asked dealer to explain/test car. I am asking for them to take me on a run - I will pay for the fuel and demonstrate getting even 36mpg+ on a motorway drive.

Fuel consumption was a big influence on my purchase decision and 27% below published figures is unacceptable and I believe illegal under trades decription act.

Would really like to collect data from all owners on what they actuall get!

Cheers

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Before asking my local Lexus agent to check my car for poor fuel consumption I emailed Lexus UK and got a fairly long and unhelpful reply, telling me much that I already knew. However a couple of points were of interest, as I cannot quote them directly I will summarise them as follows:-

1. Obviously not all cars are tested, but the chosen test car will have been carefully prepared to give as good a figure as possible.

(If this is the case I would ask if my car can be carefully prepared in a similar manner).

2. To get the best economic performance you have maximise the use of the hybrid synergy drive, which means you have to feather the accelerator frequently, namely speed up then coast a while, then press the accelerator again to regain speed, then coast again.

(I would ask is this really practical?)

I too feel Lexus are doing themselves no favours by publishing very unrealistic figures and I still cannot understand how my RX400h consistantly returned close to the published figures over four years, whilst the 450h is way off it's published combined figures in spite of the same driving techique on the same roads and same travel patterns.

Regards.

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I have previously owned an RX400h for four years and was getting close to the combined economy figures regularly, namely 32 to 33 mpg against published figures of 34.9 mpg. Admittedly thus was only achieved by not pushing the car hard and mainly driving on country roads with some town driving and very little motorway driving.

I am now driving an RX450h, which has only 4500 miles on the clock, but I find it very difficult to match what I was getting from my RX400h, even though the 450h should return about 10 mpg better for combined driving. I am driving in the same manner on the same roads as I had been with my 400h, but I'm consistantly getting only 29 to 30 mpg.

I have been around long enough to realise that manufacturers published figures are always over optimistic, but I was consistently getting within a few percentage points of the RX400h combined figures,whereas I'm not getting better than two thirds of the published combined economy figures for the RX450h.

Are there any other RX450h owners out there who are getting anywhere close to the published economy figures, or are they close to complete fiction?

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I have been running an RX450 for 6 months with 10k on the clock having previously owned an RX 300, RX400, GS450h (best car i have ever owned) and I have to say this latest model I think is the poorest one of the 4.

Fuel consumption is poor - on fastish motorway speed -80ish then it is hard to get it above 30mpg. Having driven 2 hybrids prior to the 450 I think i know how to drive them efficiently without it being a misery.

Since day one the I Pod connection has been tempremental - will never work if you try to start car in USB mode. Dealer still cannot offer a solution. I think this could well be my last Lexus. Iknow times are tough but I get the impression the dealers have been instructed to cut back wherever they can.

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I have had a new RX450h SEL premium since 1st March, the best on a trip i have had was 50mpg, but this was very hard to get, normally 35mpg, I did purchase the car for the eco fuel usage, but i must say it is the nicest to drive , not the best looking, not the best performing but a good alrounder.

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2. To get the best economic performance you have maximise the use of the hybrid synergy drive, which means you have to feather the accelerator frequently, namely speed up then coast a while, then press the accelerator again to regain speed, then coast again.

(I would ask is this really practical?)

Thats how I found I had to drive when I had a 400h on long term loan...a few years ago. I posted about my experience in great detail on this site and criticised how much you have to adapt your driving to 'use' the hybrid system as unless you lift off, the Hybrid system wont kick back in [on the 400h]. All that [additional] weight of the hybrid system, I much prefer the all petrol 300/350.

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Having changed my RX 400 for an RX 450h I have had the same experience i.e. compartively good mpg figures(32/33mpg) on the 400 and relatively poor on the 450 which is averaging 33 mpg some 12mpg short of the claimed target. Interestingly, my best tank average has been 36.5 on a recent journey of 250 miles, mainly involving motorway/dual carraigeway driving. I was travelling north to south, maybe it was downhill!!

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Just wanted to add a comment as this discussion was why I looked up this website before buying a lexus hybrid, the comments did prompt me to really think about why I was looking at a RX450 and my expectations for the car. I bought a new RX450 60 plate and am now averaging 37mpg, have had a best of 39mpg, this is mainly rural and A road driving, with some town. One long trip Motorways averaged 35mpg (70 - 80mph on M40, M25, M20). It seems to be becomming second nature now to drive more economically, I still put my foot down though, otherwise I know I would be getting better figures.

Only had the car a month but so far really impressed, was expecting 31/32 after reading the posts here and speaking to one dealer, but after speaking to others was hoping for 35/36.

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I have a 2010 RX 450 SEL and have now done 3000 miles. With careful driving in Eco mode, I can get 39 mpg. Even with mixed conditions I can get over 35 mpg. Car is fantastic when taken in isolation, but isnt the most stimulating to drive.

As long as your mindset is not to drive aggressively, it performs well. Howvever, at the end of the day, one of the main reasons was the absolute declared CO2 in relation to car tax. My previous BMW struggled to get over 30mpg and had higher CO2 so for me it was a good trade off.

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Hello chaps

Just would like to add a point, That the fuel consumption figures given are not actually recorded by Lexus,

An outside company tests every new car model and then posts its results, these tests are carried out in laboritary conditions and are the same for every mark and model, so before blaming Lexus or the dealer maybe this should be taken into consideration.

I would hazard a gues that maybe most vehicles figures are over estimated

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To those of you who own RX450h:

When you test-drove the car, did the Sales Specialist accompany you on a pre-planned route so that they could best

demonstrate how to maximise the economy on the car? Our customers have been shown how to achieve this in several

ways and are regularly seeing figures of 36-42mpg.

Best practice includes:

Anticipating road conditions to avoid harsh braking and heavy acceleration

Leaving the gear-stick in neutral while stationary drains the NiMH battery,

thereby lessening the possibility of maximising EV mode.

Removing unnecessary weight (and roof-bars and boxes!) from the car.

Ensuring all tyres are correctly inflated.

Close windows and sunroof (if you have one!) above 30mph.

Use Climate Control on re-circulation mode (this means already-cooled air is

being taken in over the condenser)

Use EV mode wherever possible (remember, the car can travel up to 5 miles at

speeds of up to 27mph on a full battery.

Turn off unnecessary accessories.

Please excuse me if some of these seem a bit obvious/patronising but we have found that

by observing the above, our customers learn a lot about the car's features and benefits

and can realise the figures above.

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My 2010 RX450H-SEi has now passed 11k miles since new, the best recorded figure is 33 MPG - this is done against fuel refilled as opposed to the computer onboard - that device gives me an average of 31.4MPG

There is no way on this God's earth that anyone will be able to get anywhere near the manufacturer's figure - without driving 'Miss Daisy!'- we've all been taken in by the hype. Having said that, I still think my car is a fantastic piece of kit and am in no hurry to change it . It's a very capable, comfortable car that isn't that common, for me this makes it worth the extra MPG....if you were that worried about the cost you wouldn't lash out nearly 50k on a car in the first place.

I didn't get taken for a test drive, they gave me an RX for the day and said it'll sell itself, which it did. And I too have iPod issues.

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22k miles done.

Tyres front at 38PSI and rears at 42 PSI

ECO mode engaged

Bracknell to Leicester and back via M25 and M1 on super plus petrol = 35.9 mpg

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It sounds like at least some of the issues experienced are most probably about driving style.

I have never been shown how to drive the hybrid correctly as the previous poster mentioned but (and I feel a little a little embarraced by even saying this) I did read the manual.

I'm ashamed to say that this tells you a number of useful points including the previously posted that should help.

I have also read in the forums here about people experiencing an increase in their MPG once they've done more mileage. Maybe it could be partly down to early days?

Highly unlikley that mine will ever see any descent fuel economy as I like the sound when you press the loud pedal too much at present.

(had to modify as the opening paragraph related to my first post as it was left from my far longer and more rambling initial stab!)

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If it helps, on the back of this forum I've been running a test on economy driving and have a few easy tips (getting me an average 37mpg easily on winding country roads with stops, roundabouts, inclines/declines and a little town driving).

First of all - I drove everywhere on cruise control. For those that don't use it much this will take some practice but essentially even if you are in a 30mph zone the car will automatically be "feathering the throttle" and eco mode will be running far more. Typically you will find that controlling the pedal yourself will result in you eventually following the speed of the car in front and not the speed limit.

As we get 10% allowance in the UK and your speedo is normally a little out I normally set cruise control at 32-33mph for 30mph zones. Going through the visual road side speed reminders flags me at bang on 30.

As an added bonus, you get to avoid being dinged by speed cameras.

Second, anticipation of the road ahead. This must be done to maintain a smooth ride with step 1 or you'll be jumping on the brakes all of the time to compensate for getting too close.

Basically look at the far distance (those of you who have had advanced driving experience should be good with this) to see where your next potential stop or slow zone is going to be and observe the following rules of the game. The aim is to cancel cruise control at just the right moment to head into a roundabout without touching the brakes AND keep the ride smooth. At first you may roll up to a junction a little quick (but you can typically feel that it will be too quick from about 3-400 yards away, just engage S and drop her down a cog to increase the kinetic charge to the battery (as the handbook puts it!), to the rest of us laymens, "changes down a gear".

Obviously I would not condone not using the brakes in an emergency (why did I feel the need to caveat/qualify that!).

Third, gentle acceleration. Get up to speed with the throttle and engage cruise control with "Set" i.e. tap down on the lever.

Fourth, most of these mpg figures are supposed to be carried out at 56mph and although there is wild speculation as to how these are conducted, you'll find in some cases cars miraculously seem to hit a sweet spot around there.

If you're on single/country roads try cruising around 56.

I actually find this quite entertaining to do and helps to focus your attention on the road conditions ahead.

Those who have done advanced driving will clearly have the additional "reading the road" tools of looking for hedge rows, clusters of street lights, reflections from headlights etc. and really turn it into an involving drive.

I'm going to stab at this not necessarily being everyone's cup of tea, but it at least works for me.

Now that's done, back to listening to the great sound from the loud pedal...I'd really missed that!

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Excellent summary of economy driving techniques, Hayabusa.

You are right about advanced driving. I can thoroughly recommend anyone applying for and taking their advanced driving test. I did mine back in 1976 and still use all the techniques in my everyday driving. The benefits are huge for a very small outlay. Vastly improved fuel consumption, less stress when you are driving, better passenger comfort, less wear and tear on your car, (especially the tyres and brakes), reduced insurance premiums and a huge satisfaction in driving generally.

Also, driving economically does not necessarily mean driving slowly. One piece of advice that has stuck with me over the years came from Jackie Stewart. "You can drive smoothly without driving fast but you can't drive fast without driving smoothly!"

So just go out and enjoy your car for far less money!

JBP

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Guys, to me, your fuel consumption for such a large vehicle sounds excellent at 30+ mpg!! My IS-F shifts around 16mpg around town, and typically around 20mpg combined. I'm going to have a look at the RX450h this week-end with a view to purchase (all RWD cars are rubbish in the snow... think the 4x4 will be more predictable, especially with about 125 less horses!) but I would say one of the best cars I've owned was the GS450h - like a rocket-ship limousine, and still returned 30+mpg, but that oh so tiny boot... :crybaby:

Cheers - Mark.

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Mark, your point is bang on, for my mind it ticks all boxes.

Economical if you want it

Big engine for performance if you want it

Big car with lots of room

Luxurious

Cheap to tax

Cheap on company car tax

I don't have to pay congestion charges when I go to London

Just been out in snow and the hybrid snow mode really stabilises things a lot.

To be fair, it was a no-brainer choice for me.

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Mark, your point is bang on, for my mind it ticks all boxes.

Economical if you want it

Big engine for performance if you want it

Big car with lots of room

Luxurious

Cheap to tax

Cheap on company car tax

I don't have to pay congestion charges when I go to London

Just been out in snow and the hybrid snow mode really stabilises things a lot.

To be fair, it was a no-brainer choice for me.

Had a right bloody job getting up the approach to the exit and out of our golf club this morning (no golf, but nice full english with the boys :winky: ) because of the 4" snow overnight. Almost as scary as diving in downhill with almost no point in applying the brakes and a couple of cars looking in serious danger of a slow-mo broadside. Enough was enough. Put my money down on an RX450h SE-L this afternoon. Derby Lexus couldn't do enough to help, and the figures all made sense with a few extras thrown-in for good measure. Looking forward to the winter driving stability, half the fuel consumption, 75% road tax reduction, a much more comfortable ride, and a lot less pain in the left ear-hole... :D

- Mark.

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The last three tanks of fuel I've been through and I'm currently averaging 25.69 MPG. Despite the slower average speeds due to the heavy snow (another couple of inches last night! ) I've noticed that the engines running almost all of the time - not suprisingly as I've got heat on, seats on and lights on all the time so it's got to be powered somehow!

Driving the RX450h in this heavy weather has been quite entertaining - the electronics sort out the traction and although I've tried the 'snow-mode' it hasn't been essential despite the 8" of powder on top of the packed ice recently - there's been a few downhill bits where it's been best to select 'first' and crawl down without the brakes.

Overall I'm really pleased with my choice, last year I was driving a tricked-out Hi-lux, I'm not completely convinced that my RX will not get stuck at some point but my RX is a damn sight more comfortable.

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I have had my 450 se-l 2009 since September.

My average mpg is around 24mpg - I reset this when I obtained the vehicle - the average mpg after refuelling is 23mpg.

This seems very very low compared to the 46mpg quoted.

Do you think there is a problem with it?

I expected 33 - 37 maybe - knowing that quoted mpg's are never achievable.

My driving is mainly local but have done a couple of runs to North Yorkshire/Blackpool with no signs of improvement.

I get approx 280 miles out of a full tank before I am running on empty.............seems very low.

Dave

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I think the Lexus fuel economy figures for the RX450H are a joke. Firstly, it is a heavier vehicle than the GS450H, with almost exactly the same engine and hybrid setup. If the fuel figures on the GS are in the low 30s, there is no way on earth you are going to get mid 40s from the RX, unless you drive 50% of the time on battery power alone. The RX is a high performance vehicle, and Lexus should give average figures based on a variety of driving styles, not just creeping around a deserted test track (or on a rolling road) at 10mph on fully charged hybrid batteries. I had an RX450H as a courtesy car for a week, and I never managed to get more than 25 in town or 31 on a long run. That is way below Lexus claims. Before this experience, I had given serious consideration to buying one. However, the poor economy and the ridiculous insurance costs (40% more than a GS450H and 10% more than an ISF in my case) made a good case against it. I went with the ISF, a totally different type of vehicle, but I'm not sorry I made that choice. The RX and GS Hybrids are great cars, but they are a total sham if you are buying to save fuel and the planet. The ISF is a gas guzzling, CO2 belching monster, with no pretences. However, the claimed Lexus fuel figures are almost spot on. The only downside is the road tax!!

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