Lies, Damned Lies And Statistics (Rx450 Mpg!)

[ALLISTER1965]

They say there's lies, damned lies and statistics but in my opinion, Lexus with their RX450h mpg figures have been plain dishonest!

In August 2012 I bought my wife a brand new Lexus RX450h SE-L for what was a discounted price of £44K. We chose the car because we liked it's understated appearance, it's soft leather, and it's all round high level of standard equipment. We were also extremely impressed by the mpg figures claimed (see below):

RX450h - Urban = 42.8, Extra Urban = 47.1, Combined = 44.8

In particular, the urban of 42.8 sounded great as my wife would largely be using the car for shopping and other local trips.

However, we have not seen anything close to the figures shown above and claimed by Lexus. Both my wife and I drive the car very steadily, yet we're only seeing about 24-25 mpg with local / urban driving, and combined around 28-29 mpg.

I suppose I never expected to achieve the manufacturer's claimed MPG, as of course I understand that these are achieved in certain conditions, but to see a drop of approximately 34% combined, and 42% around town is disgraceful and unacceptable...... I feel completely mislead and deceived by Lexus.

Has anyone else had the same problems or is there something wrong with our car?

It's only covered 900 miles, so will these figures improve as the car wears in?

Your comments would be appreciated.

Many thanks

Allister

[philthy]

If you knew manufacturer mpg figures were obtained from bench tests and not the real world, then you should have used a web site such as Honest John where you'll find average user mpg figures for the various manufacturers. Believing any car would get anywhere near claimed figures is naive

Engine Official MPG Real MPG Avg. Real MPG % 450h 44.8 mpg 34.1 mpg 76%

[Duncan Roberts]

The figures are produced in a manner required by the EU and must be published in that form: they do not amount to claims buy the manufacturer. The manufacturer has no choice in the manner in which they are carried and the results can be odd. Lexus has neither misled you nor deceived you.

No one should be fooled by them and all cars have published results achieved on the same basis. For 'real' consumption go the the likes of Honest John who has a column in the Daily Telegraph and a decent web site.

[LexusChester]

The stated MPG figures by all manufacturers (not just Lexus) are determined by a standard test carried out by the Department of Transport. The test lasts around 12 miles, with a warm engine that has covered around 1500 miles to run in. However, these figures are achievable. As part of our Lexus training we go on specific Hybrid training courses and are taught ways to slightly adjust our driving style to get the best economy. Using the EV mode etc. Perhaps you could contact the sales person you bought the car from and ask them on some advice on how to get the best from the vehicle. The last thing Lexus wants is customers that feel they have been mis LED in any way. To give you an idea on our course we achieved 74mpg from a CT200h, 47mpg from the RX and similar from the GS450h so these figures are achievable although you will have to adjust your style and not be in a hurry!

If I can be of any help to anybody on here then please get in touch.

Gwyn

[LexBri]

Allister,

I don't own a Lexus but I'm thinking of getting a used RX400h and I intend to tow a caravan with it. My current car is a skoda Yeti 1.2 TSi petrol auto and my MPG from new to approx. 11,250 miles was 33mpg (21 towing) on average. The mileage is now 11,500 and my MPG has shot up to low 40s. Don't know why but I would suggest you let the car have a few more miles before getting too concerned. Just to add, most of my mileage is local with 2 or 3 longer trips (above 200 miles) each year.

Brian

Yeti claimed mpg:

Fuel consumption - Urban 36.2 (7.8)

Fuel consumption - Extra urban 49.6 (5.7)

Fuel consumption - Combined 44.1 (6.4)

[Normski]

For me it's a case of thinking how can a car weighing over 2 tons have that kind of economy in the real world. I don't expect the RX to get anywhere close to the claimed MPG. It's a superb car that I enjoy for what it is. If I was totally driven by eco stats I certainly wouldn't be looking at Lexus.

[ALLISTER1965]

Thank you all for your comments..... Interesting what Brian says about economy improving with more miles under the belt, and what Gwyn says with regards to these figures being based on a warm engine, as many of our trips to date have been short and from cold.

However, I do not accept Philthy's comments that Lexus customers shouldn't expect to get 'anywhere near the claimed figures' WHY NOT?

I also own a Mercedes S Class (S320cdi LWB) which has just turned 3 years old. It has only covered 18,000 miles and as always achieved MPG's within 10-12% of manufacturers claims or better.

On 'Urban' Mercedes claims I should get 24.1mpg and 24 mpg is exactly what I get!

On 'Combined' Mercedes claims I should get 33.6 mpg, I tend to get around 29 mpg

And 'Extra Urban' it claims I should get 43.5 mpg, I tend to get around 37-38 mpg.

In addition, previously I had a Range Rover TD6, and once again it always achieved within 10-15% of what the manufacturer's claimed.

I understand that the 'Honest John's Review' provide some real world figures. However I suspect that these figures take in to account different driving styles, and this is the key and primary factor in giving the range from high to low. So for example, someone who drives the car quite hard should probably expect to achieve the lower end, whereas the higher end should be seen by someone who drives the car carefully and with a very light foot, which is how I would describe the way in which our car has been driven.

Why Philthy seems to think that a 40% reduction in claimed MPG is acceptable and the norm is way beyond me..... If customers can get a degree of accuracy from Mercedes and Landrover, why shouldn't they also be getting the same from Lexus?

And in response to Duncan's comments, 'The manufacturer has no choice in the manner in which they are carried and the results can be odd. Lexus has neither misled you nor deceived you'. If Lexus have so little to do with these figures and they do not wish to deceive or mislead, they certainly have a funny way of showing it, as these stats are splashed all over their literature and I'd even go as far as saying that they use them as one of the cars biggest selling points!

I'm sorry, but I do believe the marketing by Lexus in this regard is extremely misleading, and for customers to see such an enormous gap between what it widely advertised, and actual MPG in my opinion is not acceptable. Furthermore, I would say that such a sizable inconsistency is certainly not typical or representative of the rest of motor industry.

This poor fuel consumption is not the end of the world for me, as my wife will only go to the shops and the gym in this car, so I don't expect it to cover more than 5K miles per year.... However, this does not change my annoyance at being mislead.

Allister

[Duncan Roberts]

Thank you all for your comments..... Interesting what Brian says about economy improving with more miles under the belt, and what Gwyn says with regards to these figures being based on a warm engine, as many of our trips to date have been short and from cold.

However, I do not accept Philthy's comments that Lexus customers shouldn't expect to get 'anywhere near the claimed figures' WHY NOT?

I also own a Mercedes S Class (S320cdi LWB) which has just turned 3 years old. It has only covered 18,000 miles and as always achieved MPG's within 10-12% of manufacturers claims or better.

On 'Urban' Mercedes claims I should get 24.1mpg and 24 mpg is exactly what I get!

On 'Combined' Mercedes claims I should get 33.6 mpg, I tend to get around 29 mpg

And 'Extra Urban' it claims I should get 43.5 mpg, I tend to get around 37-38 mpg.

In addition, previously I had a Range Rover TD6, and once again it always achieved within 10-15% of what the manufacturer's claimed.

I understand that the 'Honest John's Review' provide some real world figures. However I suspect that these figures take in to account different driving styles, and this is the key and primary factor in giving the range from high to low. So for example, someone who drives the car quite hard should probably expect to achieve the lower end, whereas the higher end should be seen by someone who drives the car carefully and with a very light foot, which is how I would describe the way in which our car has been driven.

Why Philthy seems to think that a 40% reduction in claimed MPG is acceptable and the norm is way beyond me..... If customers can get a degree of accuracy from Mercedes and Landrover, why shouldn't they also be getting the same from Lexus?

And in response to Duncan's comments, 'The manufacturer has no choice in the manner in which they are carried and the results can be odd. Lexus has neither misled you nor deceived you'. If Lexus have so little to do with these figures and they do not wish to deceive or mislead, they certainly have a funny way of showing it, as these stats are splashed all over their literature and I'd even go as far as saying that they use them as one of the cars biggest selling points!

I'm sorry, but I do believe the marketing by Lexus in this regard is extremely misleading, and for customers to see such an enormous gap between what it widely advertised, and actual MPG in my opinion is not acceptable. Furthermore, I would say that such a sizable inconsistency is certainly not typical or representative of the rest of motor industry.

This poor fuel consumption is not the end of the world for me, as my wife will only go to the shops and the gym in this car, so I don't expect it to cover more than 5K miles per year.... However, this does not change my annoyance at being mislead.

Allister

You choose to miss one key point. ALL manufacturers are obliged in law to quote these figures in the showroom, in advertisements etc. Just as you are electing to compare one set with another you have theirs. They will quote them prominently because all manufacturers do but I would not say that any use I have seen is misleading or designed to confuse.

You have not been misled you have merely used the figures wrongly to inform your decision to buy; that your wife achieves such low returns is more connected with driving style and use than the car's capability.

[ALLISTER1965]

I think we'll just have to agree to disagree Duncan.... I'd say 85% of the miles to date have been covered by myself, so I know it's been driven very gently.

The MPG wasn't the only factor to influence the purchase, the extremely high level of standard equipment on the SE-L was another, as was the quite petrol / hybrid engine.

The Snow Mode and the RX450's AWD capability was also a key factor, (although examples of the cars performance in this area is something that's difficult to find either reviews or footage of). What I have read though seems extremely varied, ranging from excellent to hopeless!

I can live with reduced fuel consumption, however it fails abysmally in this area, then I will be disappointed.

[Radoslav Asparuhov]

I would advice to follow Gwin/LexusChester's advice - driving hybrid has nothing to do with driving other types of engines. You should learn "Pulse and Glide". My wife managed to increase the mileage of all cars we had so far for more than 20% compared to when I'm driving. The hybrid is the first she gets exactly the same as mine. She has a very light foot, but this doesn't help in this case. "Pulse and Glide" is not my cup of tea, after all the car is 2 tons, 3.3lt engine and 272hp - but compared to the RX330 - the consumption is much much better.

You can read more here:

http://www.metrompg.com/posts/pulse-and-glide.htm

[philthy]

Thank you all for your comments..... Interesting what Brian says about economy improving with more miles under the belt, and what Gwyn says with regards to these figures being based on a warm engine, as many of our trips to date have been short and from cold.

However, I do not accept Philthy's comments that Lexus customers shouldn't expect to get 'anywhere near the claimed figures' WHY NOT?

I also own a Mercedes S Class (S320cdi LWB) which has just turned 3 years old. It has only covered 18,000 miles and as always achieved MPG's within 10-12% of manufacturers claims or better.

On 'Urban' Mercedes claims I should get 24.1mpg and 24 mpg is exactly what I get!

On 'Combined' Mercedes claims I should get 33.6 mpg, I tend to get around 29 mpg

And 'Extra Urban' it claims I should get 43.5 mpg, I tend to get around 37-38 mpg.

In addition, previously I had a Range Rover TD6, and once again it always achieved within 10-15% of what the manufacturer's claimed.

I understand that the 'Honest John's Review' provide some real world figures. However I suspect that these figures take in to account different driving styles, and this is the key and primary factor in giving the range from high to low. So for example, someone who drives the car quite hard should probably expect to achieve the lower end, whereas the higher end should be seen by someone who drives the car carefully and with a very light foot, which is how I would describe the way in which our car has been driven.

Why Philthy seems to think that a 40% reduction in claimed MPG is acceptable and the norm is way beyond me..... If customers can get a degree of accuracy from Mercedes and Landrover, why shouldn't they also be getting the same from Lexus?

And in response to Duncan's comments, 'The manufacturer has no choice in the manner in which they are carried and the results can be odd. Lexus has neither misled you nor deceived you'. If Lexus have so little to do with these figures and they do not wish to deceive or mislead, they certainly have a funny way of showing it, as these stats are splashed all over their literature and I'd even go as far as saying that they use them as one of the cars biggest selling points!

I'm sorry, but I do believe the marketing by Lexus in this regard is extremely misleading, and for customers to see such an enormous gap between what it widely advertised, and actual MPG in my opinion is not acceptable. Furthermore, I would say that such a sizable inconsistency is certainly not typical or representative of the rest of motor industry.

This poor fuel consumption is not the end of the world for me, as my wife will only go to the shops and the gym in this car, so I don't expect it to cover more than 5K miles per year.... However, this does not change my annoyance at being mislead.

Allister

You shouldn't expect to get near to claimed mpg figures simply because anyone with an ounce of noggin knows they aren't obtained by real world driving and rather by a standard bench test which all manufacturers are required to do. I do not think it is acceptable to have a 40% discrepancy in claimed and actual mpg figures but then I don't for one minute take manufacturer's claimed figures as gospel. YOU, like the rest of the car buying public, have to accept that manufacturer claimed mpg figures are unlikely to be achieved in the real world even with a worn in engine and driving like Miss Daisy, and if you want to drop your engine out, stick it on a bench test and run it at the claimed rpm, it is the only way you'll get near or to those figures..

[LexusChester]

Also I thought I would direct you to this piece. This shows you how there is inconsistency in the testing. To give you an example, a CT200h has MPG of 68.9 in the UK. In the USA it has an mpg of 42. See this link for the RX450 USA figures http://www.lexus.com/models/RX/detailed_specifications.html

Also, this is how the figures are calculated for the UK.......

How is the fuel consumption test conducted?

• 
  The test is outlined in Directive 93/116/EC as amended by Regulation (EC) 692/2008, and provides results that are more than representative of actual average on-road fuel consumption than previous tests. There are two parts: an urban and an extra-urban cycle. The cars tested have to be run-in and must have been driven for at least 1,800 miles (3,000 kilometres) before testing.
  
• 
  Urban Cycle
  The urban test cycle is carried out in a laboratory at an ambient temperature of 20^oC to 30^oC on a rolling road from a cold start, i.e. the engine has not run for several hours. The cycle consists of a series of accelerations, steady speeds, decelerating and idling. Maximum speed is 31mph (50km/h), average speed 12mph (19km/h) and the distance covered is 2.5 miles (4km).
  
• 
  Extra-Urban Cycle
  This cycle is conducted immediately following the urban cycle and consists of roughly half steady-speed driving and the remainder accelerations, decelerations, and some idling. Maximum speed is 75mph (120km/h), average speed is 39mph (63 km/h) and the distance covered is 4.3miles (7km).
  
• 
  Combined Fuel Consumption Figure
  The combined figure presented is for the urban and extra-urban cycle together. It is therefore an average of the two parts of the test, weighted by the distances covered in each part.
  

My apologies. I thought it was a warm engine but its not. However I think everyone will agree that at an average speed of 12mph a hybrid will get amazing fuel economy. Is this true to real life???? the whole test is 6.8 miles. on a rolling road at Uk summer time temperatures. no wind resistence, no hills. no stopping for traffic lights etc. Once you know this you realise the test is flawed. The biggest victims will be the people who buy plug in hybrid vehicles that claim up to 200mpg. but based on this test they will be in electric for most of the test!!

[Duncan Roberts]

I think we'll just have to agree to disagree Duncan.... I'd say 85% of the miles to date have been covered by myself, so I know it's been driven very gently.

The MPG wasn't the only factor to influence the purchase, the extremely high level of standard equipment on the SE-L was another, as was the quite petrol / hybrid engine.

The Snow Mode and the RX450's AWD capability was also a key factor, (although examples of the cars performance in this area is something that's difficult to find either reviews or footage of). What I have read though seems extremely varied, ranging from excellent to hopeless!

I can live with reduced fuel consumption, however it fails abysmally in this area, then I will be disappointed.

We are indeed going to disagree: You are putting your confidence where it does not belong. This is merely another example of Eurocrats sticking their noses in where they do not belong to no useful outcome other than prevent alleged lies being put forward to describe performance. We have the ASA which is perfectly capable of dealing with this type of issue.

[philthy]

Also I thought I would direct you to this piece. This shows you how there is inconsistency in the testing. To give you an example, a CT200h has MPG of 68.9 in the UK. In the USA it has an mpg of 42. See this link for the RX450 USA figures http://www.lexus.com...ifications.html

Also, this is how the figures are calculated for the UK.......

How is the fuel consumption test conducted?

• The test is outlined in Directive 93/116/EC as amended by Regulation (EC) 692/2008, and provides results that are more than representative of actual average on-road fuel consumption than previous tests. There are two parts: an urban and an extra-urban cycle. The cars tested have to be run-in and must have been driven for at least 1,800 miles (3,000 kilometres) before testing.
  
• Urban Cycle
  The urban test cycle is carried out in a laboratory at an ambient temperature of 20^oC to 30^oC on a rolling road from a cold start, i.e. the engine has not run for several hours. The cycle consists of a series of accelerations, steady speeds, decelerating and idling. Maximum speed is 31mph (50km/h), average speed 12mph (19km/h) and the distance covered is 2.5 miles (4km).
  
• Extra-Urban Cycle
  This cycle is conducted immediately following the urban cycle and consists of roughly half steady-speed driving and the remainder accelerations, decelerations, and some idling. Maximum speed is 75mph (120km/h), average speed is 39mph (63 km/h) and the distance covered is 4.3miles (7km).
  
• Combined Fuel Consumption Figure
  The combined figure presented is for the urban and extra-urban cycle together. It is therefore an average of the two parts of the test, weighted by the distances covered in each part.
  

My apologies. I thought it was a warm engine but its not. However I think everyone will agree that at an average speed of 12mph a hybrid will get amazing fuel economy. Is this true to real life???? the whole test is 6.8 miles. on a rolling road at Uk summer time temperatures. no wind resistence, no hills. no stopping for traffic lights etc. Once you know this you realise the test is flawed. The biggest victims will be the people who buy plug in hybrid vehicles that claim up to 200mpg. but based on this test they will be in electric for most of the test!!

USA and UK gallons are different quantities. I can't remember off the top of my head which is bigger, but it may account for the difference.

[LexusChester]

1US gal lqd = 0.83267420UK gal

Quite right there is a difference but nothing like the 50% difference in quoted figures.

Here is the USA test................

The "city" program is designed to replicate an urban rush-hour driving experience in which the vehicle is started with the engine cold and is driven in stop-and-go traffic with frequent idling. The car or truck is driven for 11 miles and makes 23 stops over the course of 31 minutes, with an average speed of 20 mph and a top speed of 56 mph. The "highway" program, on the other hand, is created to emulate rural and interstate freeway driving with a warmed-up engine, making no stops (both of which ensure maximum fuel economy). The vehicle is driven for 10 miles over a period of 12.5 minutes with an average speed of 48 mph and a top speed of 60 mph. Both fuel economy tests are performed with the vehicle's air conditioning and other accessories turned off.

Quite different to the UK!

[noby76]

They say there's lies, damned lies and statistics but in my opinion, Lexus with their RX450h mpg figures have been plain dishonest!

In August 2012 I bought my wife a brand new Lexus RX450h SE-L for what was a discounted price of £44K. We chose the car because we liked it's understated appearance, it's soft leather, and it's all round high level of standard equipment. We were also extremely impressed by the mpg figures claimed (see below):

RX450h - Urban = 42.8, Extra Urban = 47.1, Combined = 44.8

In particular, the urban of 42.8 sounded great as my wife would largely be using the car for shopping and other local trips.

However, we have not seen anything close to the figures shown above and claimed by Lexus. Both my wife and I drive the car very steadily, yet we're only seeing about 24-25 mpg with local / urban driving, and combined around 28-29 mpg.

I suppose I never expected to achieve the manufacturer's claimed MPG, as of course I understand that these are achieved in certain conditions, but to see a drop of approximately 34% combined, and 42% around town is disgraceful and unacceptable...... I feel completely mislead and deceived by Lexus.

Has anyone else had the same problems or is there something wrong with our car?

It's only covered 900 miles, so will these figures improve as the car wears in?

Your comments would be appreciated.

Many thanks

Allister

Hi Allister, this is not the first time this topic has been raised have a read at this http://www.lexusownersclub.co.uk/forum/index.php?showtopic=78890 . all car manufactures fuel consumption figures are achieved using the best ways possible to extract more frugalness/economy from the engines be it diesel, petrol or hybrid powered cars during official mpg testing but in real world driving we all know figures could either exceed or decrease by 5 - 10 mpg depending on a cars engine health and ones driving style and even the roads and time at which one drives can contribute to this factor. dont forget an RX450H weighs in at over 2000kg and if your journeys does not require the car running on the hybrid batteries say 70-80% of the time in urban driving then I am afraid you will not achieve the stated urban figures. your quoted figure of 24-25mpg sounds about right as the car is running mostly off the engine rather than the batteries. although you have achieved close to the stated urban figures in your Merc and Range Rover google or log onto other car forumns and you will read threads of owners not achieving close to the stated figures in thier Diesel cars aswell. I mean i dont drive like Miss Daisy nor do i drive like i stole my IS300 but on a good day i could achive 33 mpg combined driving from my IS300 and on a bad day i get 22mpg on the same combined cycle driving all boils down to my driving style at that time. I am not saying you or the wife races the RX everytime you get into the car but maybe the journeys you make does not really suit the car to extract more from the hybrid system to give good mpg. all i say is hybrid works best in highly congested places like London where more stop and start driving is experienced and if one does not live or drive in those areas then you wont reap the benefits of going hybrid as you will spend most of the time on the 3.5 litre V6 engine pulling a car weighing over 2000kg.

[Greyanglia]

Hi Alister,

I have a '59 reg 450h with 33k on the clock which I have owned since June. The previous owner never reset the fuel consumption and it shows 29mpg over the life of the vehicle so far if this helps.

This morning I picked up a loan 62 reg facelifted 450h from my local dealer with 1800 mls on the clock and the total fuel consumption figure shows 31mpg which gives some confirmation of typical mileage by different drivers and styles.

I do think it is unfortunate that the 450h does have such a wide disparity between official figures and real life for all the reasons raised in previous posts. The 450h is by no means not the only car to suffer in this way although it does p*ss me off a bit to see Lexus trumpeting the fuel consumption figure of 44.1 mpg combined in their current ad for the facelift model. I know they can legally do this as they do not come up with the figure but they know full well no owner has a cat in hells chance of getting anywhere near that in real life!

Shame as it is a great car and I am really enjoying it so far. I guess you just have to think of the 450h as 30mpg vehicle plus a bit more if you drive really carefully but enviromentally friendly compared to its rivals (!!).

ps. for all pre facelift owners I was pleased to see (from a resale perspective) that apart from the front bumper, slightly different steering wheel, a couple of buttons and a centre console that actually opens to 90 degrees there is

no apparent difference to the previous model!

Michael

[ALLISTER1965]

Hi Michael

Finally...... It's not just me who considers this huge gap in MPG a bit annoying. Once again, it's not that the figures are slightly out or hard to achieve, it's that they're miles away!

As previously mentioned, my Mercedes always gets close to what the manufacturer claim, hence my disappointment with Lexus...... In fact only this morning, I returned from London in my S Class, spending most of the 180 mile journey travelling at around 75-80 mph, yet still I achieved 37.5 MPG!

Taking into account that Mercedes say I should get 43.5 MPG extra urban! (and this is probably based on travelling at a steady 56 mph) by comparison, I think Lexus should be embarrassed to be getting it so wrong, and to be using these hugely inaccurate figures as such a prominent marketing tool.

Let's just hope that one day, Lexus can at least get to somewhere within 20% of what it claims......

Allister

[HASSELBLAD]

They say there's lies, damned lies and statistics but in my opinion, Lexus with their RX450h mpg figures have been plain dishonest!

In August 2012 I bought my wife a brand new Lexus RX450h SE-L for what was a discounted price of £44K. We chose the car because we liked it's understated appearance, it's soft leather, and it's all round high level of standard equipment. We were also extremely impressed by the mpg figures claimed (see below):

RX450h - Urban = 42.8, Extra Urban = 47.1, Combined = 44.8

In particular, the urban of 42.8 sounded great as my wife would largely be using the car for shopping and other local trips.

However, we have not seen anything close to the figures shown above and claimed by Lexus. Both my wife and I drive the car very steadily, yet we're only seeing about 24-25 mpg with local / urban driving, and combined around 28-29 mpg.

I suppose I never expected to achieve the manufacturer's claimed MPG, as of course I understand that these are achieved in certain conditions, but to see a drop of approximately 34% combined, and 42% around town is disgraceful and unacceptable...... I feel completely mislead and deceived by Lexus.

Has anyone else had the same problems or is there something wrong with our car?

It's only covered 900 miles, so will these figures improve as the car wears in?

Your comments would be appreciated.

Many thanks

Allister

Well Allister, I have done exactly the same as you!

Two weeks ago we sold our RX400h (which was really good on consumption at 33mpg average over nearly five years) and bought a virtually brand new RX450h.

During the first week of 'learning' about the new features, we averaged 55.1mpg! It is still on the screen. I also did a brim to brim to check the computer and it was good to 1mpg.

Since then we have settled down to 37mpg on fair cross country driving, 33mpg on cold starts and short runs up to 6 miles) and have yet to check on Motorways.

A couple of days ago, the car did a 90 mile round trip with four adults in it and averaged 39mpg in very mixed traffic.

The only way I can get it to go into the 20's is to floor the accelerator in Normal mode and brake hard( which negates the hybrid system!) at the last minute for any and all obstructions.

Previous to buying the car, I was loaned an F Sport RX (which we didn't like at all!) but it averaged 36mpg on an 80 mile run, with no problem at all.

Have you had a hybrid before? Do you know how to pump back the kinetic and potential energy stored in the car? Do you use Eco mode?

If you do these things and still get your lousy figures, then take the car back......it is very faulty.

Do you live in the Southern counties? If so, maybe we could meet up and I'll show you my RX actually achieving these figures.

[ALLISTER1965]

Hi Hasselblad, hope you're enjoying the new car.....

Thank you so much for your very kind offer to meet and advice, until recently I was living in Haslemere, Surrey which would have probably worked well, but unfortunately due to work commitments in the North, I'm now living up in sunny Yorkshire.

Your fuel consumption sounds fantastic, I'm not getting anywhere close to that but having read your e-mail I think I may be missing something. In reply to your questions: No I've never owned a hybrid before, and I don't know anything about how to pump back the kinetic and potential energy stored. I know the car has an ECO mode, but yes you're right, I've never used it and don't know when to either.

Maybe I need to look at the manual.... It's difficult finding time, my wife and I work 6-7 days a week on our e-commerce businesses and the RX450h manual (as you yourself will know) seems to have more pages than the Old & New Testaments put together!!

I feel I can't ask you to explain about the Kinetic energy pump back as it sounds quite complicated and I don't want to take up too much of your time, however if you can forward me any links explaining how this works I would be extremely grateful.

Re: the Eco mode, I'll look in the manual for more info.

Just one question though, as you sound like an experienced RX owner, have you had any RX experience in snow?

If so, how does the car perform?

And do you change over to snow tyres in the winter?

Many thanks for your previous response / help.

Kind regards

Allister

[HASSELBLAD]

Hi Allister,

Maybe a few, modestly meant, words to help relieve the frustration you are rightfully feeling?

Firstly, put the official mpg claims to one side---------as other respondees have said, they don't mean a lot as their tests cannot readily be emmulated by mere customers!

I'll try to keep this brief so don't latch on to generalisations if they suggest variance with the gist.

1. The petrol in your tank is where all your initial energy comes from.

2. That petrol is converted to heat, movement and electrical energy by your Atkinson 3.5 litre V6.

3. Mostly the energy is used to accelerate the car up to a given speed (when it now has Kinetic Energy) and/or to increase its Potential energy by moving it up a hill.

4. All non hybrid cars then WASTE both these sources of energy! Much of it in heat in their brake discs or in transmission losses in the engine and drive train.

5. The full Hybrid car SCAVENGES this energy and recovers much of it as electrical energy to store in the 300v Battery under your back seat.

6. It then uses this 'FREE' energy to drive two sizeable electric motors that save you using yet more of your precious petrol.

Now, you, the driver, can influence that Scavenging considerably.

7. You must look well ahead on the road and evaluate what is happening that influences your energy recovery.

8. When you see or know that you are to slow down, then change down to a lower gear (the 450h has 6 gears and you should use them to slow the car). This is good practise at junctions,roundabouts and so on.

Don't worry unduly about this optimisation, as simply taking your foot off the accelerator will generate good levels of energy recovery anyway.

9. All four brakes on the 450h are Regenerative. This means that when you brake gently, they will recover energy for the traction Battery. So, AVOID heavy braking as this uses the discs and you waste a recovery opportunity.

10. The above savings are aimed at Kinetic Energy recovery. When you start to go down a hill, you now have Potential energy available too!

Again, use the gearbox and again use gentle braking.

11. You can watch all this happening on the 8" central screen and I would suggest that you leave the 'Energy' screen up (the one with the car wheels etc displayed) until you gat the hang of it).

When you accelerate from a standstill, try to just use the recovered Battery energy. You will not suceed, but it saves a lot of petrol trying!

USE the ECO mode (select with the rocker switch on the right of the steering wheel.). Make sure your special tyres are set to at least 36psi......preferably 38psi

Doing the above will save a lot of fuel and it enhances tyre and brake life. I never replaced any tyres or pads or discs(or anything at all, come to that-----super reliability) in nearly five years with our 400h.

I would recommend that you warm the car up thouroughly, go to the top of a small hill(that is psychological!) zero your consumption readouts and then drive in a relaxed manner doing the things outlined above.

After 20 miles or so on a reasonable country lane, see what mpg you now get?

Hope that helps even though it is not the whole story.

By the way, as for Lies, damned lies et al...........I was born and bred in Yorkshire and there is no way you can insert the adjective 'sunny' and be credible!

Ironically, I now live a 'stone's throw' from Haslemere.

Cliff

[HASSELBLAD]

Hello again Allister,

A few general answers to your other questions.

The new car is excellent. Refined, predictable and economical. I did try the X5 and the ML and had a look at the Audi and Volvo.

In the family we have a new Range Rover Overfinch (17mpg) a Defender diesel (25mpg) a new Lexus IS250C (29mpg), and an Aston Vantage Volante and a Convertible Mini Cooper S.

Up until recently we had a Bentley Continental GT (16mpg), a 300C with the 3 litre Mercedes V6 diesel fitted with a Brabus SD6 engine management system (the best diesel, by far, that I have ever owned!). We have also owned several Discoveries and a mix of jaguars and Mercedes.

The 450h (and the 400h before it) have ALWAYS been the cars family members have left the drive with!!!

As for snow use, we don't get a lot of that round here. My preference would always be dedicated snow tyres and then chains. However, snow tyres cost an awful lot as you usually end up buying wheels as well. And it is a fuss having to switch them over.

Our 400h was a mixed bag in snow. As it always started from rest on its two electric motors, there was massive torque available and that could be disastrous. Otherwise, with a gentle right foot, it did OK. Nothing like the Defender, though. Horses for courses.

The 450h apparently recognises this and there is a dedicated SNOW driving mode that automatically controls the motor torque.I have no experience of it yet.

I must say that I have found ground clearance the most important feature in snow but when I have been defeated it has ALWAYS been due to other totally unsuitable vehicles blocking the road!

One last point, I am quietly assured by my local Service guys that my fuel consumption is by no means the best they have seen! And I thought I was doing real good.

Cliff

[ALLISTER1965]

Hi Cliff

You had me in stitches with your comments about sunny and Yorkshire.... I've nowhere to go on that one.

Thank you for all the info on maximising energy in order to improve fuel economy, I'll have a go with those tips. I was interested to read about your range of cars, a nice selection indeed. I'm not suprised that your family tend to leave the drive with the Lexus, which is exactly why we bought it... I think it's probably because it's effortless and relaxing to drive. My wife hated driving our old Range Rover mainly because of it's size, although I absolutely loved it, covering 110,000 miles in just 4 years.

Thanks once again for all your info.

Best regards

Allister

[ALLISTER1965]

Hello again Cliff

Just one more thing..... As I now live in (not so sunny) Sheffield(a City which holds the title of worst roads in the UK!)I decided to reduce the tyre pressure down to 35psi in order to survive the potholes.

Do you think this was a bad idea?

Allister

[HASSELBLAD]

Hello Allister,

No, 35 psi is not a problem. I am running at about that pressure too.

If you want to get every last bit of mlleage from a gallon, then the higher pressure will help but it is much more important to get the driving style right.

Today, Lexus Guildford lent me a new petrol GS250. I really could not squeeze any more than 26/27 mpg out of it. Having picked my RX up in the afternoon, I readily did 38mpg over the self same 50 miles!

I have been passing Haslemere all day long!

I remain delighted.

By the way, sorry to hear that you have been in hospital and I do hope you are now well.

Best regards,

Cliff