I only get around 26 mpg in my 2008 LS600hL on the interstate at a steady 75 mph, so the highway mileage is definitely a bit lower than the standard LS460s. But in town, which is the majority of my driving, I average around 22 mpg. That's where the hybrid technology makes a difference. I think many LS460 owners probably average closer to 16-17 mpg in the city. That 5-6 mpg difference may not sound like much, but it's actually about a 40% improvement over the 16-17 mpg for the standard LS.

But to be honest, I really don't care that much about fuel economy in my 600. Like most LS600 owners (I would imagine), I simply enjoy the amazing power/torque/smoothness that comes with the 5 liter V8 coupled with the electric hybrid motors. I also enjoy all of the amenities that come standard in the LS600 (pretty much every LS460 option plus the sweet leather dash).

 

I have been getting at least 30 on the hwy since my purchase myself and must say it is pretty darn impressive for a two ton plus car with a V8 that does not even have cylinder deactivation and or start-stop mode at red lights.

Most of this stellar mileage is due to the very aerodynamic shape of the car (0.26 which at least at the time of introduction tied it for being the most aerodynamic sedan on the road) and the 8 Speed Automatic which allows for a very tall 8th gear for interstate travel.

Regardless, this is stellar engineering and amazing considering the size and weight of the car as it matches many 6 cylinders and even perhaps a poorly designed 4 cylinder.

 

Nope. The LS600 weighs 800 lbs more than the 460, due to the hybrid battery pack and AWD. The extra horses of the 5.0 make up the weight, but no gains in performance.

 

Very impressive highway mpg indeed.
With stock 17 in wheels, I was getting 28 - >30 mpg from SoCal to Las Vegas at 75-80 mph with 4 adults. City/hwy driving was mid 22 - 24 mpg.
Now with 20s, I get high 25- 26 mpg. Still very good considering the bigger and heavier set of wheels. Hwy/city driving 18 - mid 21 mpg depending on my lead foot.

 

Stock wheels are 18s btw, no 17s available for the LS460.

 

Thanks for the correction.
My previous G37 has 17 in and replaced with 20s as well.

 

Having been underneath the still new-to-me 2008 LS 460 L replacing an alternator for a few hours, I can say a significant contributor to the unusually high MPG highway figures for this car is the underbody cladding.

Pretty much everything but the exhaust is covered by either plastic or metal 'sheets', which smooths air flow. You might not think it's significant, but having a 'dirty' underbody, aerodynamically-speaking, is a huge efficiency killer.

For a current production car, I cannot see anyone making the underside any smoother, honestly. All that stuff costs money and 99.9999% of people won't know/care/understand.

However, having the engine turn only 2K RPM at 80 MPH is a huge aid. The top-most gears on these nearing-double-digit-gear automagics need to be the _third_ overdrive. Don't shift to that gear unless there are some very restrictive criteria met. At this point, I want just off-idle at say, 75-85 MPH. These engines put out enough torque to make this work without being an annoyance.

Also, I'd rather drop up to 6-7 MPH without a downshift on grades and the like. Better yet, I'd prefer the shift-it-yourself bit obey what I tell it to do.

Hold 1st until redline, then bounce off said redline? Yes.

Come to a stop in 8th and subsequently not be able to move from a red light after exiting a freeway? Yes, that too.

If you're not paying enough attention to use them as a manual automagic, then you shouldn't be controlling the transmission in this fashion.

Also, using cruise-control actually lowers MPG. You can see/anticipate road changes the CC can't. It's purely reactive, which is the antithesis of high MPG. Conservation of momentum!

Everyone should have to 'do time' in an 80's Mercedes W123 four or five cylinder, naturally aspirated, diesel.

You can't appreciate a 20 second 0-60 time until you've experienced it.

Oh, and an '85 Cadillac Fleetwood Brougham d'Elegance with the HT4100 is an appropriate substitution. Comfy as your living room, and about as quick.

 

Nice post loaded with excellent information. Agreed about cruise and having cars that have had both "radar/intelligent/et al/" cruise and plain ole cruise (vastly prefer), I would reckon in a little over 20 years of driving that I have used cruise control around 5% of total interstate travel over 100s of thousands of miles and having gone through 46 of the lower 48 and Hawaii.

Things like aerodynamics under the car is exactly where Toyota/Lexus having such vast resources shines like a lighthouse. Things like this and them scrapping the literally almost ready for production LF-A when constructed of aluminum to redo it with in house carbon fibre production are what separates them say from Nissan where R&D cannot even be compared and who are also pretty much controlled by the French.

 

On average this is what I get in my 08 LS460. One time I got around 35mpg from Bakersfield to Fresno CA in the slow lane (65mph), love this car!!

 

Uhh yeah. How about some pics of the tank average. I mean seriously, the LS460 is not averaging 30+ MPG on the highway unless your on very flat terrain with a nice tailwind. There are situations that can be ideal for mpg but if the car could actually consistently achieve this mileage it would be rated a lot higher. Also, the computers are pretty notorious for telling you one thing but your actually getting something else. Hand calculating a long trip is the way to get realistic mileage and even then many factors come into play. Weather / wind, temperature, speed, tire type, inflation, fuel grade, winter or summer fuel, AWD or RWD, etc.

 

I get nothing close to 30 mpg, even with just freeway driving. It's more like low to mid-20's. Marin County, SF Bay Area. The freeways around here aren't level for the most part. My LS460 becomes "thirsty" when the accelerator pedal is pressed. Also, i don't think my usual freeway trips are long enough to build up mpg. When I take longer trips, freeway mileage is generally better.

Not really complaining; I just can't imagine getting 30 mpg in my area.

 

bingo my friend, highway 99 is my primary commute in central cali: completely flat, no hills, just a nice view of cattle and agriculture lol

 

Oh man I'm going to Walnut Creek for a meeting in may, if there ever was time to not share my mileage it would be in the Bay Area lol. I hate waiting in Livermore or going over the Altima where you get zero MPG for hours on end, only once I timed leaving S.F. before 3pm to avoid traffic. I use my SUV there since I'm afraid of those large trucks and the hills!

 

Fortunately, I'm able to mostly drive during non-rush hour traffic. I don't have a work commute. It's the terrain IMO that contributes to the lower mpg compared with what some other folks are getting.

 

Ah understood, that's great too! I commute 400 to 900 miles a week for work. I had chevy volt that I traded in for this car, but this car just continues to impress.