Fuel Consumption

[BigJon]

As some of you will know I've had my LS400 two weeks now and I'm still testing it, as it were,

anyway my wife and I have just got back from a weekend in Bangor (didn't we have a lovely time) and I filled up to the very top in Telford as we left on Saturday and refilled, to the very top, on our return on Sunday (this afternoon) 279 miles later.

I used 48.13ltrs thats 26.78mpg, amazing for a 4ltr V8.

My son has a Peugeot 205 1.9GTI and he only gets 25 mpg.

Ok I love the smoothness of this car and I'm quite happy to poodle along in it, this test was mostly at 70mph on cruise control, driving to Llandudno in the evening for an indian meal, a bit of town driving looking for parking places (they need to be quite large) and one or two short bursts of speed when required, in other words economical driving.

I'm well impressed with that mpg because next year we've hired a cottage on the Isle of Skye and thats a long way.

So far to sum up = It's comfortable for me (I'm a big fat bloke), fast when I need it (I enjoy that part), smooth and quiet to travel in and has reasonably economical fuel consumption.

I'm sure I'm going to find some bad points about this car but at this time I'm thoroughly enjoying myself.

BigJon

[peter026]

Glad you're enjoying the car John :D That's not a bad MPG figure for a 4 litre

[MJM444]

Glad you're enjoying the car John :D That's not a bad MPG figure for a 4 litre

Hi

Will agree about the fuel consumption regularly get 30 mpg on a long run

Two weeks ago on a run back from Bournemouth - 212 miles - via M27/M3/M25/A1 rural roads for the last 20 miles to Christhurch in Cambridgeshire (on the Norfolk border) recorded 32.1 mpg i.e. kept to the 70mph speed limit and no holdups - was able to use the cruise control probably 50% of the journey

My vehicle is a 1998 MkIV LS400 - 50,000 mileage

[chips229]

Hi,

Thats good mpg,its the short trips that kills the mpg,my driving was mainly short trips when i had my LS.Like you say on a run it was really good with the mpg.The short trip mpg was what really made me decide to change cars.

But dare i say i think my next car will be a mk4 LS when the prices come down.

Chips.

[maneesh]

that's good.. :D not many folks know how economical it is for a 2 ton limo!

[BigJon]

Yes I'm glad to hear others get good consumption, the next couple of weeks or so will be just pottering around to the supermarket, chip shop, the common to walk the dogs and so forth so I'll fill up again after that and compare the difference.

Cheers all,

BigJon.

[graham8370]

that's good.. :D not many folks know how economical it is for a 2 ton limo!

like Bigjon,picked up my MK1V 2 weeks ago.Drove back 406 miles in exactly 6 hours and returned an amazing 33.4mpg. Am I HAPPY

[simontaylor]

Last year I had a luchtime meeting in Wigan, so I was not pressed for time while driving up from Surrey. I tried to cruise at 60 and came back via Wexham and a visit to demon tweeks. 36 mpg !!!

Worst case was the kids half term, racing around on short trips taking them all about around town between friends houses, 18mpg. Still not bad for a 2 ton taxi.

[Chris Skelton]

:D :D ....and the pleaure of driving such a car makes it worth it anyway! B) B) :P

[JellyBean]

36mpg? I don't belieeeeeve it.

[BarneyTT]

36mpg? I don't belieeeeeve it.

I managed 31-33mpg with cruise control set at 73mph and the odd bursts of speed for overtaking etc. So 36mpg@60 sounds possible.

[Alex JB]

I made 33mpg with the cc on @ 70mph. :)

work and back 10 miles each way, all week in light trafic 300 miles from 70 litres = 19.4mpg :(

[just rolling]

36mpg? I don't belieeeeeve it.

I managed 31-33mpg with cruise control set at 73mph and the odd bursts of speed for overtaking etc. So 36mpg@60 sounds possible.

On the subject of fuel consumption, are the figures from lexus correct? I have a series 3 and Lexus says it does 21mpg around town, which I think mine is not too far off. The series 4 and LS430 manage 16mpg around town, which is a big drop. I was considering upgrading, may just buy a cleaner series 3 instead!

[GoldfingerLS]

36mpg? I don't belieeeeeve it.

I managed 31-33mpg with cruise control set at 73mph and the odd bursts of speed for overtaking etc. So 36mpg@60 sounds possible.

On the subject of fuel consumption, are the figures from lexus correct? I have a series 3 and Lexus says it does 21mpg around town, which I think mine is not too far off. The series 4 and LS430 manage 16mpg around town, which is a big drop. I was considering upgrading, may just buy a cleaner series 3 instead!

Figures from Lex are probably correct. After around 1995/96 (from what I can remember off the top of my head) manufacturers, in line with new EU rules, had to change the way they quoted fuel consupmtion figures. I can remember reading the back pages of What car back in 1995 (the pages with the red header where they have the specs for every car make/model). Every car would have 2 numbers. The 21mpg was probably the lower number but the lower number was always over optimistic. After 1995/96 all cars were quotes with 3 mpg numbers: urban driving, Extra Urban and a combined figure.

On my MK4 i can get:

16 mpg around town in London traffic. If traffic is heavy (as is usually the case in London) and with the air con running, I can often get as low as 14.5 mpg, just depends on the traffic

18 to 23 mpg when i drive a mix of town driving and A406 (50 mph driving) and/or driving through clear road at night (i.e. with very little start stop)

30 to 34 mpg on the motorway. I can get 34mpg with the cruise control set to 70 mph. As soon as you decide to open up the taps on that V8 on the motorway, you can say goodbye to 30mpg and better.

[maneesh]

in my old LS, I managed to get 19mpg with CC set at 120mph (In germany of course).

[hitchers]

in my old LS, I managed to get 19mpg with CC set at 120mph (In germany of course).

The following are my best estimates of fuel consumption for my 1998 Mk 4 LS 400.

Local 22 mpg

Local plus motorway 27 mpg

Motorway 30mpg

On each trip I filled the tank at the beginning and the end.

I have had my Lexus for three months and am still grappling with tank avaerage, etc. so use this simple method to work out consumption.

Hitchers

in my old LS, I managed to get 19mpg with CC set at 120mph (In germany of course).

The following are my best estimates of fuel consumption for my 1998 Mk 4 LS 400.

Local 22 mpg

Local plus motorway 27 mpg

Motorway 30mpg

On each trip I filled the tank at the beginning and the end.

I have had my Lexus for three months and am still grappling with tank average, etc. so use this simple method to work out consumption.

Hitchers

[JellyBean]

About spot on, I'd say. These 36mpg claims must be obtained by people whose arithmetic is faulty or whose imaginations are fertile.

[DC_LS400]

About spot on, I'd say. These 36mpg claims must be obtained by people whose arithmetic is faulty or whose imaginations are fertile.

Ah well I must disagree here, I'm sure you can do the maths. Filled up to the brim, drove just over 200 miles to Sheffield, filled up again and had used £25 of fuel. Now I tend to use Sainsbury's Super unleaded which cost me 85.9 pl but in Sheffield the same was 89.9 so a good 20p extra per gallon. So at approximately £4 to a gallon that would equate to 6 gallons. And that was definately not my imagination or incorrect calculations. Oh and it's a 1990 LS400. :)

[GoldfingerLS]

About spot on, I'd say. These 36mpg claims must be obtained by people whose arithmetic is faulty or whose imaginations are fertile.

Ah well I must disagree here, I'm sure you can do the maths. Filled up to the brim, drove just over 200 miles to Sheffield, filled up again and had used £25 of fuel. Now I tend to use Sainsbury's Super unleaded which cost me 85.9 pl but in Sheffield the same was 89.9 so a good 20p extra per gallon. So at approximately £4 to a gallon that would equate to 6 gallons. And that was definately not my imagination or incorrect calculations. Oh and it's a 1990 LS400. :)

I would agree with Mr DC_LS400 here. And for owners of the Mk4 LS400, there is not even arithmetic involved since the Mk4 has a trip computer !! (Not sure if the Mk1, Mk2 and Mk3 have trip computer ?) All you have to do is re-set the 'Average' reading at the beginning of your journey and by the end you can see your average - as simple as that.

I can see that 36 mpg at 60 / 65 mph is plausible in my view from an LS400, at least the Mk4 anyway.

All LS400s were built equal, but not all have been maintained equal during their life. I can think of 5 basic service items right now off the top of my head that, if not serviced properly, WILL adversely affect fuel consumption.

[ian11]

27.8 ltrs /4.56 = 6.09 gallons which equates to 32.84,which is damn good for a 4ltr lump of a motor like these,but unless you have the same route with the same driver,same weather and road conditions,which is highly unlikely !! this thread will run and run.

ps, mine does 43 to the gallon on the m/way at 70, ask the wife !!!!!!! how do you think i can justify the fuel costs, "honest dear its better on fuel than my old shed of an escort and look at the ride quality"

and ive owned it since may and not filled it to the brim yet,the garage i use has a fifty quid limit on overnight fills,got fed up with the scroats doing a runner with full tanks !!!

Ian.

[JellyBean]

Ah well I must disagree here, I'm sure you can do the maths. Filled up to the brim, drove just over 200 miles to Sheffield, filled up again and had used £25 of fuel. Now I tend to use Sainsbury's Super unleaded which cost me 85.9 pl but in Sheffield the same was 89.9 so a good 20p extra per gallon. So at approximately £4 to a gallon that would equate to 6 gallons. And that was definately not my imagination or incorrect calculations. Oh and it's a 1990 LS400.

This is all rather vague. And I make this between 32 & 34 mpg. Which is still NOT 36mpg!

As for those who rely on their trip computers to calculate mpg, these things are always a trifle optimistic.

I still say 36mpg in an 1800kg car with a 32-valve, 8-cylinder engine with auto transmission is just not on (silence, Maneesh!); I reckon 32 is about top whack and amazing enough, really. Especially to someone who used to run Jaguars with carburetters, where 20mpg on a run was cause for great satisfaction. (As was a month without something falling off, but that's another story.)

I promise to shut up now. I just believe accuracy is more useful as information, that's all.

[simontaylor]

Jellybean, I admire people that will put their heads up over the papapit, stand up for themselves and their belifs until proved incorrect and not just sitting back quietly and saying nothing.

I keep all my petrol receipts and input them into a spreadsheet since I got my LS400 18 months ago. This calculates mpg per tank as well as overall mpg and pence per mile. I can assure you that my arithatic is correct, I got a grade A at "O" level, even this is worth about 9 GCSEs these days.

HOWEVER, most sincere apologies to you and every one else who has been trying to get 36mpg. I mis read my data, actually I 'only' got 31mpg. I have not been on here for a few months, so I missed all your good posts.

Again, sincere apologies for my mistake.