Lexus Rx400h Thread

LexusRX400H · October 15, 2011

Hi All,

I have recently picked up a '2006 RX400H with around 41k on the clock, a few prior owners, well maintained and from a dealer.

This may sound quite unbelievable to you, based on your email threads, but I am getting mind blowing mileage.

In week one I drove like I normally do (I am a reasonably fast driver) and got very poor mileage. However I tried a few tactics to see how best to keep to the 99.9 mpg reading.

This week, I decided to see what the best I can get from it is. I have done 128.64 miles (London to Slough and back twice), driving in the left lane, mostly keeping to the 99.9 mileage reading. I have expended a quarter tank of petrol. It cost me £72.62 to fill up the tank, I calculate that I have got 44.09 mpg. I have another car which is a 3 ltr diesel and I don't think I get that kind of mileage. The Lexus has a 3.3 Petrol engine (Hybrid with an electric engine/motor on top) and I cannot believe the figures! Granted, I've been driving very carefully, and it's put an extra 20mins-25mins on my journey. Also granted, I've only had this for a short while and who knows what mileage I'll get going forward. But so far - unbelievable! That's better mileage than a Fiat Punto 1.1! (http://answers.yahoo.com/question/index?qid=20090817124016AAwecJg)!

I got a caution earlier this year for driving too fast - with this car I hope I don't get a caution for driving too slow!! :)

Hut49 · January 11, 2012

Just to add something to this thread that has been quiet for nearly 12 months! I just completed two tanksful in our new purchase 09 plate RX400H with around 20k on the clock. The first tank I frequently explored the performance and got a measly 21mpg. The second one I tried to be as economical as possible and with a mix of rural and motorway driving (using the accelerate and lift off technique) I got to 28.3. No where near the 33.2mpg that I got from my Jag XF 3.0D S averaged over 10,000 miles. Frankly I'm very disappointed because the salesman bragged that the RX400H should easily match the Jag's fuel economy. Nowhere even close. However the driving experience is very good and the practicality of the loadspace (the real reason for making the change) makes it just about acceptable.

RegalJohn · February 2, 2012

Just to add something to this thread that has been quiet for nearly 12 months! I just completed two tanksful in our new purchase 09 plate RX400H with around 20k on the clock. The first tank I frequently explored the performance and got a measly 21mpg. The second one I tried to be as economical as possible and with a mix of rural and motorway driving (using the accelerate and lift off technique) I got to 28.3. No where near the 33.2mpg that I got from my Jag XF 3.0D S averaged over 10,000 miles. Frankly I'm very disappointed because the salesman bragged that the RX400H should easily match the Jag's fuel economy. Nowhere even close. However the driving experience is very good and the practicality of the loadspace (the real reason for making the change) makes it just about acceptable.

I find that there is a big difference between summer and winter figures. In winter the engine is kept running more to deliver heat to the cabin. I average around 28 mpg in winter and 32 in summer.

Vitali Roshkani · February 8, 2012

Hi i am a new member of this forum and ferst of all what to say Hi to everyone.. I finally managed to get my self something what i was waiting for long time, now its happend -))) i am a proud owner of Lexus RX 400h SR. its 2007 and has 44 000 on the clock and full lexus dealer history, with multimedia pack on it. I been driving it nor for 2 weeks and only one thing i am not happy with its MPG. i drive very smooth, keep my feet of acceleration, but getting max 20mpg. And i meen it, i drive slow and very careful on acceleration, but for some reason it dont help. I been trying to monitor how hybrid work and looks like this is a problem comes from, some time it will kick in in about 35mph speed, some time it will not even on 7mph . tryed everything keept my hitting off, completely off, but again, just about 20MPG. I have 12 month warranty and going back to Lexus dealer. They arranged with me day driving, they wana see how I drive. Any advice? what can i ask them to check? what can i do regarding fuel consumption?. Thank a lot.

JBPRX400h · February 9, 2012

Hi Vitali

It might be worth trying the ISC (Idle Speed Control) learning procedure that has been well documented on the USA Lexus forum.

http://us.lexusowner...opic=58930&st=0

It worked on our 2006 and our 2008 RX400h.

Regards

JBP

sherryman05 · August 21, 2012

Hi, I'm new and bought a lexus RX400h 57 plate with 50k. It runs lovely but I noted the fuel economy issue and with careful driving step / off it now seems to do about 33mpg which is quite good. I noted that someone said that the tyre presures are critical and when I checked them they were on 36 psi all round rather than the 32 recommended. This seems low? What do other owners inflate theirs to?

ColinBarber · August 21, 2012

I normally keep mine around 34 to 36.

DarrenR · August 23, 2012

I think I'd like to put in my two pennies worth here,

I was under no illusion that driving a 3.3 V6 was ever going to cheap, put I offset the cost of fuel by the comfort and pure joy I get from driving mine, I commute to work and most of that time I'm in traffic but I'm sitting in a big Pembroke leather chair setting the climate to my needs and listening to my favourite album on the Mark Levinson stereo, if I wanted better mpg I would have bought something smaller.

Seems to me that the more time you sit in traffic the better the mpg, but I am only into my second week of ownership so maybe the gloss will fade but at the moment I love it!!

sherryman05 · August 24, 2012

Hi, agree with you Darren, but just wanted to know where I stand being a new owner. I just drove up to Newcastle via the M62 from the Wirral at distance of 180 miles. I put 32 psi in the tyres as per the recs. The car did 36 mpg on what is a hard route really. On the way back - I came back with 36 psi on what I thought was an easier route along the A69 and down the M6. The car recorded 33mpg ! The steering is heavier on 32 - or maybe I just imagined it on the M62? Either way - the car is not like a traditional car that does lousy mileage in town but better on the motorway. It likes coasting with a light touch on the accelerator. If you put the pedal to the metal it costs you though and you will get the lousy mileage recorded above? I found at 75-80 - and driving normally it does around 32.5 - and I am happy with that. For Yanks - remember that the Uk Imperial Gallon is bigger than the US Gallon so our figures probably dismay you. I think that the UK Gallon is about 15% bigger?

DarrenR · August 26, 2012

Hi Sherryman

Yes the us gallon is smaller than the uk gallon, who knew!!

Last week I was driving around Cornwell and Devon with 2 adults and 2 kids in the car and was averaging around 30 to the gallon, but that was motorway and fast A roads so not really a fair test for me because most of my driving will be commuting to and from work and driving to Tesco at the weekend, If I can still get 30's I will be happy!

But as I said in my earlier post its more about the driving than the petrol I out in, if that makes sense.

Actually I started off with 32 psi all round but reading the posts on here I changed to 34 and it does seem to roll better when you back your right boot off, which means you enter stealth mode sooner and get even more mpg!

So today I washed, clayed, polished and waxed and just noticed it took me about 6 hours! but looks really nice.

sorry I forgot to say i have only had my lexus for about 3 weeks so I am very much a newbie on all of this.

nice chatting

Darren

DanD · August 28, 2012

^{Hi... in 3 months of ownership, I have averaged 29mpg (UK), doing a 50-50 mix of urban and motorway (75-80mph). I can't say that I have been particularly careful, although I have learnt to give the engine short bursts in order to make the most of the electric power. I also use the cruise control as much as possible. Otherwise, the radio (or CD) and aircon are always on and there is always at least one device charging in one of the sockets. I am surprised that some of you have only achieved low 20s... but equally astounded that others have reached low 30s... just how slow have you been driving?}

mburstyn · February 1, 2013

So I have now owned my '08 RX400h for a week. My daily run of 18 miles is almost entirely on a 50 mph restricted road after a 1 mile side street approach. So getting onto the main road and setting the cruise control to 50 has enabled me to get just over 37 mpg on each direction.