DB S600

Hello:

I am the owner of a 2004 LX and I feel - as of recently - that my MPG has gone down and that I am refilling the tank all too often. In fact, I have always felt that the tank of my vehicle was insufficient because prior to the LX I had a 1999 Denali - and I didn't recall refilling as much as I did and currently do with the LX.

I have a few questions:

1. Is there any recommended way to improve MPG on this vehicle <-- I know, I know this is probably the magic question for everyone these days, but anything in particular for this vehicle. I have 35k miles on the truck and have performed all routine maintenance

2. Has anyone heard of adding an extended gas tank? Anything that would not be obtrusive to the interior of the vehicle. Something to compensate for how much gas this think actually eats - so that I don’t have to refill so often

3. I know that the manual says that premium should be used - and I have used this octane thus far. But how about a lower octane fuel? I know too that this might cause a decrease in MPG - but can this be substituted without damaging the vehicle / engine?

4. Would adding a rear spoiler improve MPG - or is this simple a styling cue?

and one last one... 5. I know that the 2006 has a revised engine management system (increased horsepower) - but do the '06's also come with improve fuel economy?

Thanks so much! And insight would be much appreciated!

JD

V8_Fan

What is the actual fuel economy you're getting now? You need to record the gallons filled and mileage off the odometer to get an accurate reading. Best is to calibrate the odometer against those 1 mile signposts on the freeway. Only then can you be confident at your fuel economy. Did you happen to switch brands of gasoline lately? I think you guys are now using ethanol additives, right? Ethanol gives fewer mpg than pure gasoline (contains fewer btu's). Not sure how it compares to MTBE. Both give less mpg than gas.

All the Landcruisers and LX470's sold in Australia come w/ the factory subtank, a 15 gal tank that fits above the spare. I'm not sure if it'll fit on '03+ US LX/LC's, as the charcoal canister (a rectangular box on the driver's side to the left above the spare) might get in the way. One can buy aftermarket aux. tanks for the LC/LX that hold 40 gal (need to move the spare onto the bumper), plus one can replace the main 25 gal tank w/ a 40 gal. So max capacity is 80 gal. If you use a 40 gal in the rear, you need to upgrade the suspension springs....more tricky w/ the LX due to the AHC.

Jurwin

The 1999 Yukon Denali has a fuel tank capacity of 30.5 gallons. The LX470 has a fuel tank capacity of 25.4 gallons. The LX470 is EPA Mileage Estimates: (City/Highway) Automatic: : 13 mpg / 17 mpg. So it's not that economic from factory. But if your MPG is even lower than when the car was newer there are a couple of things you can do to improve your mileage. I also like to mention something interesting. Over seas models of LX470/Land cruisers have dual tanks. They come with a main tank (25.4 gal) + sub tank (12 gal) bringing the total to 37.4 gallons. You can buy the factory sub tank and install it but it's a bit of work. They fit between the factory spare tire and the body letting you leave the spare right where it is. Installation requires some fair mechanical skill, and installation of a transfer pump, and associated plumbing.

Now onto 10 easy tips to improve gas mileage.

Tip #1 - Adjust the air pressure in your tires
An underinflated tire will cause more rolling resistance since most of the tire is in contact with the road. Not only will this decrease fuell effinciency but it will also cause premature wear of the tires. The recommended tire pressure is imprinted, in relief, on the sidewall the tire.

Tip #2 - Use the correct oil viscosity
Using the wrong viscosity oil can increase drag and produce extra load on the engine and oil pump.

Tip #3 - Get an alignment

Tip #4 - Change your spark plugs

Tip #5 - Change or clean the airfilter

Tip #6 - Inspect the cap and rotor for buildup ( Only aplies to a vehicle utilizing a distributor. Does not aply to LX470)

Tip #7 - Remove extra weight.
Empty the car of unnecessary weight. On my Land Cruiser I have my third row seats removed and it's stored neatly in my garage since I barely even use the third row seatings.

Tip #8 - Take care of that check-engine lamp
If the check-engine lamp is on take your car to your local dealer and have them fix it.

Tip #9 - Keep those injectors clean
We always have been firm believers of a clean engine is a happy engine. The better you take care of your engine the better it will take care of you. Over time oil and gunk can build up on the injector nozzle inhibiting proper fuel fuel atomization. Worse yet, dirt in the nozzle can cause the injector to leak and waste fuel. Cleaning the injectors can be as easy as adding a fuel injection cleaner additive at your next fill up at the gas station.

Tip #10 - Change your driving style.
Frankly many of us drive with a heavy right foot. Easing into the throttle as you accelerate and letting off and coasting up to a red light can substantially increase the vehicle's fuel economy. If you are performing a long cross-country drive use cruise control. Even though you might think you are holding the acceerator steady the car's electronics will do a better job. Also turning the PWR button off might also help saving gas.

valgs350

iTrader: (1)

That PWR button!

LOL

toyotafan2

First of all, try to limit small stop/go trips that are less than 20 miles in length, severely eats away at mileage, two adding an extended gas tank can actually worsen mileage again, all your doing is adding extra body and fuel weight, extra gallons for mileage trade off is terrible, three listen to the manual, certain engines (especially Lexus, Infiniti, BMW, Mercedes-Benz, and Acura models) that have any type of electronic modules controlling the engine will require premium. It can screw up the regulators and severely affect power and torque. The spoiler would be negligent in terms of adding MPG, it may allow friction to push down more on the car, adding some downward force (High-School Physics 101), along with a little aerodynamic performance improvement, but pratically no improvement on gas. Lastly, yes the VVT-i installation can improve MPG on highway by 30%! This of course requires no use of air conditoning, use of cruise control and traveling on a level highway with no steep inclines or declines in road angle, carrying around no unnecessary cargo and payload and 5 people at most in the car. Overall, it can improve mpg anywhere from 3 to 13% total (that's what Cadillac claims on their VVT technology in the new Escalade, I don't believe them.) Anyway, hopefully that information is helpful to you. Enjoy your LX, I wish I could get a sweet Lexus SUV, I may be able to one day if I can get a job as an engineer designing the planetary gear set for Toyota SUV automatic transmissions....very wishful thinking I know.

ArmyJoe

This just in, LX470 gas milage is no good. Thats ok though, it has plenty of power. Would be suprised about those 10 simple things, that indeed help with the milage. Here in Iraq, I jumped in a 04Land cruiser the other day and was looking around. The contracted people here drive tons of them. And under the hood it had... the good old trusty inline 6. I know when I drove the older 450, it didnt pack the punch I kinda hoped for> I didnt get to "Drive" this LC, but with a little less power than the V8, add the fact that is pretty well up armored.. and I am sure its not too pretty. Anyways I have to agree that its just plain not good from the factory, and the price is paid for having the power added to the what 5 or 6000 lb truck?

Hope you get your milage resolved to at least the 13/17.

Cheers, Joe

panni

As mentioned above tire pressure seems to help a lot. A friend monitored his pressure closely for a few months, and also used Nitrogen for top offs. He noticed measurable improvements. This was in Chicago with significant weather changes. One day it can be 60-70 degrees F and the next it can be 10-20 degrees. Dealing with that today, 2" of ice covering everything after last nights storm, and tomorrow's forecast is into the 70's.

What about tire size, is it possible to get a slightly narrower (less footprint) tire, further improving MPG? How about a moderately priced narrower tire and replacing more often to keep a stiff tire on vehicle?