DavidinCT

2001 LS here, Driving to work about an hour ride, cruse when I can (maybe about 30% of the ride with cruse on it, 65-70mph), I will see around 22-24 mpg. This is with some heavy traffic sometimes.

If I take my car, and go on a long ride with cruse on 65 with no change in speed, I will see 25-27....

So, it all depends on the commute. Always put premium in the car when I can (95% of the time I do)

Is this highway or back roads with stop and go traffic ? On back roads or mail roads, 16-17 is not uncommon, with highway you should see closer to 20+....

notwealthy

I live and work right at sea level. You're probably on to something with the slow driving. The bulk of my mileage is on the freeway, but I probably spend more time at stoplights in town. I think my average speed was in the high 20s. I might run a tank of Techron or VPower through it to see if that cleans things out at all.

Lavrishevo

iTrader: (1)

Yeah. The average speed kind of speaks to how we drive. Mine is similar. 34 mph and I tank average usually 21 - 22 mpg. I like the Lucas injector cleaner. Also, running 93 octane does improve the performance and a slight mpg improvement. This has been argued back and forth.

chunkyda

22.56 mpg for the past 110,000 miles. I live in a rather unpopulated part of Florida, drive 25 miles to work each way, air conditioning is almost always on 9 months out of the year.
Chart shows my calculated mpg and car computer mpg are typically within 3% of each other so dash display is pretty accurate and resets itself showing tank average at each fill up.
Worst mpg was when my wife drove for a few days with her lead foot back in 2009 and July 2014 when my twin boys participated in a teen driver course all day conducting manuvers in a parking lot and idling in park with the a/c on. When I picked them up the computer shower 11 mpg but driving on the rest of the tank brought tank average up to 19. Best mpg is of course on the freeway with cruise control on. If I drive in city stop and go, the computer does show 18-19 mpg but then a bit of time on the freeway brings it up, I'm glad I don't live in a big city for more reasons than car mpg.

jayclapp

The trip computer is nice to use for instaneous mileage, which you don't get otherwise.

But, it is not really as "accurate" as using actual miles and how much fuel you put in the tank at fillup. This is because the only thing that counts financially is the cost of fueling over the actual miles you have driven. While this might not be more "accurate" than the computer, it is the only thing that is really meaningful.

Bocatrip

I'm sure I posted before, but with about 95% city driving, the few times I actually calculated the mileage, I might get 13mpg. That doesn't bother me considering how comfortable and quiet the ride is.

aqbill

2006 LS and 1300 miles back & forth to Rock Island, Illinois from northwest Alabama. Secondary roads from here to Paducah KY and then Interstate. Overall, 28 mpg with over 29 on Interstate (2/3rds of trip) and 26 on secondary roads. AC on the whole trip and 70 mph on Interstates and 55 to 65 on secondary roads. Good car on the open road and I drive it as though I'm going to have it for many years...and I am.

Cheers,
AQBill

Natey2

2005 LS430 with about 100K miles.
Around 16mpg average.
Lowest was around 12.5
Best was around 24.5

Historical:


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mikedc26

05 With about 800 pounds in the trunk 19-22 highway

Lavrishevo

iTrader: (1)

If I stay around 70 - 75 I can get 26 - 28 mpg all day long. I do get better mileage when using 93 octane fuel. My best mileage has always been with fuel additive on good 93 octane gas. Think your LS doesn't like higher octane? Try filling up with the best octane you have available and add a bottle of the Lucas injector cleaner. Do this on an empty tank. I promise you will see excellent mileage if measure it on the trip computer. Averaging 30 - 32 mpg on the highway is what I get at about 70 mph when running an octane boost.

Have you?
Cleaned your maf, throttle body and injectors?
How is your air filter?
Type of tires and pressure.
Elevation and type of driving.

Natey2

That's awesome.
Lexus only advertises the 2005 LS430 doing between 18 and 25 mpg:


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Lavrishevo

iTrader: (1)

In tip top shape the LS430 definitely gets better mileage then advertised. You boys out in CA have only 91 octane and tons of ethanol everywhere. Ethanol also reduces the octane level. I'm telling you, if you don't think octane matters on a high compression LS430 engine try filling up like I said. 93 + Lucas fuel treatment or an octane boost. Not only will the car feel more responsive and powerful but you will get excellent mileage vs regular fuel. The more the timing can advance due to the computer not detecting any knock the more efficient the motor will be. My LS400 was the same way. These engines love higher octane fuel.

https://www.clublexus.com/forums/ls4...great-mpg.html

writes123

Out in SoCal, driving to LA from the Inland Empire. Averaged around 31-32 mpg using Arco aka BP 91 going 65 mph as an average occasional 60 mph slow downs with occasional 70 mph passing. City driving with lights around 14.5 mpg using ECT SNOW mode.

jamsvet

Just got back from roundtrip San Diego to San Francisco. Up on I5 down on 101. 22mpg on midgrade.

rxonmymind

Went down the coast and back home for a round trip if 200 miles. Mostly cruised at 75 mixed with extra lead foot now & then. Keep in mind these were on bald run flat tires. Talk about a jarring & jittery ride. Anyway just purchased some Continental Contact control sport A/S and probably would have done a 1-2 mpg better.