bluestar

The '95 S420 has a 26 gal tank, while the '92 LS400 has a 22gal tank. There is a difference here. But if you are getting a 2mpg higher on the heavier S420 (4700 Ib vs 3759 Ib), maybe the aerodynamic coefficient of drag is lower on the S than on the LS !!! But 24mpg on a '92 LS is darn good. On my '99 (with the 5-speed vvt-i) the best I have ever done is 22mpg at 80MPH cruise speed on a 150mile trip. I'd be happy with 24mpg and not diss it.

LIGHTYEAR

Hi Guys,

at a steady 75 mph on the motorway, over long journeys, with some agressive overtaking and the occassional crawl in traffic my 1995 LS400 returns about 28 - 30 mpg.

However, the imperial gallon (UK) is slightly larger than the US gallon so maybe that explains some of the difference.

I am shocked to hear some of you are getting less than 20 mpg on a long haul, obviously around town efficiency deteriorates pretty rapidly!

Please bear in mind that petrol is around $5.50 per gallon in the UK - more than double what you lucky people in the US pay !!!!

retrodrive

Aerodynamics is better on LS...in fact it is better then Corvette's. Hard to believe isn't it?

LIGHTYEAR

It is amazing how low the drag factor is on the LS400, from the very first MK1's upto the latest LS430's.

It just goes to show that the designers put the wind tunnel technology to very good use for this car, as much as they did for the Japanese Bullet Train and that baby goes faster than any Lexus !!!

Indeed the drag coefficient on the first generation LS400 still compares favourably to many of the latest model BMW's and MB's.

You have to hand it to those Japanese designers, it may look sometimes like a snub nosed brute - but boy does it work.

ychachad

Yes, 1 US gal = 3.78 litres
1 Engligh Gal = 4.55 litres
so your 28-30 translates into 23-25 mpg, but your cost per mile is 2.5 times higher!!!!

Y. Chachad

LIGHTYEAR

Yes YCHACHAD, thanks for the explanation, that makes sense, but what really does not make sense is the way we are so ripped off by our government(s) here in the UK for the price of fuel.

80 pence in the pound goes straight in the pocket of the Chancellor of the Exchequor - nice work if you can get it !!!

Might explain why we do not have as many nice big engined motors as you people over the pond !!!

Lvangundy

Driving habits have A LOT to do with it..

I could get 100 miles to the 3/4 mark if I really try..I've got a picture to prove it.

I don't think the owners manual specifies getting 24MPG even on highway. It might be the 'MAX' but I'd guess you're driving at 55mph the whole time.

24MPG? I'm a little skeptical..but if you are getting 24MPG your LS must be in excellent engine condition.

SQ-LS

Interesting my fathers S420 doesn't get any where close to 26 mpg.

Specs wise the 95 S420 wieghs 4,700 lbs and gets 20 mpg hwy while the 92 LS400 weighs 3,700 lbs and gets 23 mpg hwy.

Maybe you just got an exceptional MB and at the same time a good LS too.
Consider yourself lucky!

ychachad

Been doing the trip from South Bend, IN to Morgantown WV for 1 year now, twice a month. Fill up just on the IN turnpike, drive straight to MT, 2 rest stops on the turnpike plaza, all interstate. No going through the town. No question about accuracy. Yesterday I got almost 500 miles before the fuel light came on. Again, 24 mpg.
Y. Chachad.

ychachad

My 1995 MB S420 was owned by a 70 year old, and it was his vacation car!!! It is literally a brand new car that happens to be 8 years old.

Gabeshell

Ychachad,

I see in another post that your LS400 has 180,000 miles on the clock. I think that considering you have that kind of mileage 23 mpg is outstanding. Since the MB has only 70K on the clock I can understand the mpg difference.

rybikowsky

Comments have been deleted

ychachad

Thanks

LS400

Ychachad, just some background history. The LS400 was the mass-produced luxury vehicle that set the standards when it came to gas mileage (along with everything else practically). Before the LS400 (and during the early years of the LS400), BMW and Mercedes Benz cars were getting horrible mileage (way less than 20 MPG). The typical mileage of the LS400 is around 20 MPG (depending on how hard you drive the car). Personally, 24 MPG going 70 MPH-consistent is an excellent ratio!

So now that the competition has caught back up with Lexus, you can see the vast improvements of gas mileage (along with reliability, dependability, etc.) from BMW and Mercedes. It could you (driving style) or your MB, but 26 MPG contant is a rare breed (even with today's MB models).

But also remember, your LS400 is more than a decade years old while your Mercedes Benz is not as old (and you did say it was never driven hard from its previous owner).

If you think your LS400 has more mileage potential, I'd recommend getting it checked out by a trusted mechanic or dealer. Have them do a full-checkup on the engine as well as check the o2 sensors.

Previously, on my 1993 LS400, the o2 sensors were broken, thus draining gas.

ychachad

Thanks for a wonderfully positive post, I'll certainly take your suggestions to heart.