Gas Mileage

[Guest]

Here is a real rookie Q. What kind of gas mileage should I expect on a 98 LS400 city and highway? Mid-grade or premium? I hope there is no need for like-gold premium.

I can't believe how much I am learning from your great posts, thanks guys!

[nc211]

I think you can get away with mid-grade, but it likes premium and is recommended. My 95' has a 4 gear transmission, as where yours has 5. To use as a judgement, my 95' gets around 19-20 in the city, and 25-27 on the highway. Using your cruise control is a huge help! I think Blake told me that the 5 gear tranny gets around 28-29 highway? But if you put your foot in it, well, it is a V8 after all. Not as thirsty as the old 5.0 Mustang engines, but still can get thirsty.

[LexusLooker]

Congrats on your new purchase! I have a 98 also and it's a great car. Like NC says, if ya put your foot in it, it'll suck gas. But if you drive fairly normally, you can easily get in the mid to upper 20s on the highway, at least according to the computer, which I have a sneaking suspicion is a bit optimistic. I have a 60 mile commute, about 80% highway and 20% stop-and-go highway, and the 'puter tells me I'm getting 25 with the A/C on and 27 with it off and light traffic. In town, it drops down to 22-23, but I'm not in town much, so I bet that's a bit high. I took a long road trip 2 weeks ago, and on one leg with the A/C off, it was telling me 30.4. The leg back home with the A/C on said 28.2. All that said, I went a little over 500 miles on that tank and filled up with right at 19 gallons - which comes to a little over 26 according to the calculator. So I'm guessing the 'puter may be a couple of MPG optimistic. But basically if you're careful, you can get amazingly good mileage. Enjoy the car...and these guys are great on here.

[nc211]

Baja, on a side note, one thing you should do is make sure the air filter is clean as a whistle. This helps big time not only in mpg, but in engine smoothness and pick-up. I've noticed on mine that it gets pretty dirty every 6 weeks or so. That big ole' engine can suck in some air! I just hit it with my shop vac and while I have the plastic air intake off, I will usually rinse it out with water and let it dry.

[alsalih]

Baja, on my 98 I can run any grade fuel, however I've noticed that it runs smoother and it gets better MPG with 93 octane so this actually offset the added cost for me. Lexuslooker, I was also getting MPG in the high 20's range when I first got my car however I quickly realized the reason, my fan clutch was "free spinning" as it had lost it's internal clutch oil! Once I replaced the fan clutch my MPG went down by 2 to 3 MPG especially during the summer when it's engaged most the time. Just something to look for (my temp gauge never went above half despite that!!). Also, regarding MPG, your driving style can really make a big big difference, I tend to cruise at 75 to 80 mph which really eats up the fuel.

[Guest]

Again, many thanks for the tips and insights! Truly incredible!

I am a pretty normal sedate driver so getting mid-twenties highway and close to 20 in town will be jsut GREAT. I am coming from a Honda Accord. Great car but the two are miles apart.

Incidentally, my Baja handle is kind of an inside joke just for me. The guy I am buying from bought from my brother a few months ago and is now buying Mercedes (thanks for [not] thinking of me bro.!) Anyway we were joking back and forth about how in the meantime he had taken this car to Baja and cut out the door pillars, painted numbers etc... He said he would have the pillars welded back by this weekend when I pick it up. I asked him to use flat-black when painting out the numbers so I could just chalk my own as needed for upcoming races. All a joke but it just seemed fitting when signing up for the site. Thanks again, hope you can put up with the novice Qs I will have. B.

[SKperformance]

I get 8L/100km all highway

10L/100km city/higway mix

12/100km all city

now 12/100km city/highway mix with my 20 inch rims.

Best increases in milage from keeping the tiers at 50psi and adjusting my lead foot.

here is the conversion to mpg

KM Per Liter Miles Per Gallon (U.S.)

8.00 19.12

9.00 21.51

10.00 23.90

11.00 26.29

12.00 28.68

13.00 31.07

14.00 33.46

15.00 35.85

[Leadfoot]

and adjusting my lead foot.

←

You rang?

Seriously I find that 60 miles an hour gives me superb economy on long distance ~28mpg. This is in a '92 with 150K miles on motor. However I cannot get better than 21 mpg urban no matter how slow I take off from the lights and how carefully I drive.

Luckily for me gasoline comes out of my entertainment budget!

Baja, I will probably get flamed for saying this but I have found the offroad capability of mine very good, although if the police ever find out it was me I am in big trouble!

[LexusLooker]

Great story about your name, Baja. Especially funny about the flat-black space for numbers. Hope your friend gets the door pillars back in straight. And Lead Foot, I also do some minor offroading. All this talk of Michelin vs. Continental vs. Vogue tires, pfft. I'm thinking of some Mickey Thompson Mudders and a nice lift kit. Forget slamming the car, I want to go UP! I was on some dirt trails the other day and took some pictures, but I also figured I'd get flamed. So this is our secret...shhhh.

[nc211]

Great story about your name, Baja.  Especially funny about the flat-black space for numbers.  Hope your friend gets the door pillars back in straight.  And Lead Foot, I also do some minor offroading.  All this talk of Michelin vs. Continental vs. Vogue tires, pfft.  I'm thinking of some Mickey Thompson Mudders and a nice lift kit.  Forget slamming the car, I want to go UP!  I was on some dirt trails the other day and took some pictures, but I also figured I'd get flamed.  So this is our secret...shhhh.

←

Now that's my kind of member! I'll bring the beer, you bring the mud! :D

[LexusLooker]

There you go! Come on down. We'll find some mud and we can break in your new tires and new suspension parts. I tell my Jeep bud (a natural born mudder from the Smokey Mountains) that the towhooks on the back of the Lex are to pull his stuck out of the mud!! I guess the cupholders in the LS hold a beer can well? You crack me up.

[akewlguy]

Others here state that closed windows (less resistance) improves MPG. I also question the increased drag with bigger tires. This may have a minor effect on decreased MPG.

Cruise control is a sure way to increase your MPG. I have a 93 that seems to get 21 around town and 23-24 on the highway. I do about 74 MPH on the highway in cruise control.

Reguarding the premium vs regular or plus debate. If you break down the cost then premium is the way to go. Typically premium is .30 cents more then regular. So if it costs 2.75 you are looking at about a 10% increase in cost. Now this may seem like a lot but if you typically put 2000 miles a month on the lexus its about $20 dollars to follow the rules of engineers that built the best car on earth.

MY LS deserves premium. Cheers

[Guest]

Baja, on a side note, one thing you should do is make sure the air filter is clean as a whistle. This helps big time not only in mpg, but in engine smoothness and pick-up. I've noticed on mine that it gets pretty dirty every 6 weeks or so. That big ole' engine can suck in some air! I just hit it with my shop vac and while I have the plastic air intake off, I will usually rinse it out with water and let it dry.

←

Great suggstion, I'll keep that in mind!

[akewlguy]

My air filter must be disgusting!! I am off to clean at 2AM.

[914lps]

Oh GOD!!!!

Lets not get into the regular or perm thing again.

In short becouse you car is computer contolled you can "run" it on low grade gas. But can and should are not the same. 91 will make the car happy and you will also get more mpg with it then reg. :chairshot:

For off roading I get 8 mpg in my ford truck! :cries:

This is why I drive the Lexus everywere exept off road or to take the boat to the river! B)

I have a lead foot and a 91 LS400. Running on long drives (200 to 800 miles) I get 21 to 22 mpg at speeds of 85 to 90 mph. I have no doubt 55 to 65 would get much better mpg.

Around town i have no idea almost all my miles (90%) are hwy.

I clean the air filter about after every long drive. You would be amazed at the bug collection you get. Butterflys, bees, greasshopers, and once part of a small bird.... My dirving is mostly open hwy from state to state. Arizona, Nevada, California, and Mexico (yes I know Mexico is not a state .

[Guest]

On the Air Filter...

I have not even been under the hood and am going today to pick up the car and drive it 700 miles back home. So checking the air filter sounds like a pretty good idea. Anything tough about FINDING the air filter? I presume it is pretty standard, nothing hidden? (I know that sounds incredibly naive not to have even checked out the car but my brother had it for 7 of its 7.5 year life and his best friend has had it the rest. Both have been nuts on maintenance at the dealer.)

[Guest]

Sorry screwed up this post !

[LexusLooker]

Baja, there are no stupid questions here. We've all been in the position of not knowing where stuff is on these cars. The filter isn't too hidden, but it's not a big round donut with a snorkel on it on top of the engine, either (as I'm sure you know). It's just not super easy to get to the first time, and you'll need a 10mm wrench or socket. It's on the far left side, towards the front, as you face the engine. There's a website you need to know about: www.lexls.com. The guy (and I can't remember his name) has done some great tutorials with pictures. His car is a Gen I, so some of his tutorials don't exactly fit our 98s, but they're super close in many cases, and are very well done. He also has a great comparison of the different models. You'll soon be able to tell a 97 from a 98 from 500 feet. His tutorial for an air filter change is here: http://www.lexls.com/tutorials/maintenance/airfilter.html

I'm also amazed at how quickly the filter gets dirty. I used to go 30K in other cars. Now 15 seems too long. But it's good news. That just means that grit isn't getting into the engine.

[vyhanh]

Hi,

I just went 140 miles on 1/4 tank (from full to exatcly 3/4 mark on gas gauge). How much mpg is that? I guess I can calculate but think that someone knows this quicker

TIA

VH

[VBdenny]

I have a K&N air filter on my LS. It seemed to pick up a mile or two a gallon. On my last Interstate run, I got 24.7mpg but I was running about 85-90 much of the time. I have no idea what kind of gas millage these cars get when you drive the speed limit since I have never done it. I use only premium since I don't care how much gas costs.

[blake918]

Baja, I will probably get flamed for saying this but I have found the offroad capability of mine very good, although if the police ever find out it was me I am in big trouble!

 

←

LOL I took a similar piture of my car at some property that we have. I don't really take it off road though; atvs are more fun offroad!

[lexluxury]

Do you manually clean the air filter or just replace it? They cost 20 buck or so and changing it out every six weeks could get expensive. Had no idea that I needed to check it that often. The last time the mechanic switched mine out, he had trouble getting to it and getting it back on (this is a 1st Gen LS400 btw).

Oh GOD!!!!

Lets not get into the regular or perm thing again.

In short becouse you car is computer contolled you can "run" it on low grade gas.  But can and should are not the same.  91 will make the car happy and you will also get more mpg with it then reg.  :chairshot:

For off roading I get 8 mpg in my ford truck!  :cries:

This is why I drive the Lexus everywere exept off road or to take the boat to the river!  B)

I have a lead foot and a 91 LS400.  Running on long drives (200 to 800 miles) I get 21 to 22 mpg at speeds of 85 to 90 mph.  I have no doubt 55 to 65 would get much better mpg. 

Around town i have no idea almost all my miles (90%) are hwy.

I clean the air filter about after every long drive.  You would be amazed at the bug collection you get.  Butterflys, bees, greasshopers, and once part of a small bird....  My dirving is mostly open hwy from state to state.  Arizona, Nevada, California, and Mexico (yes I know Mexico is not a state  .

←

[akewlguy]

1/4 tank at 140 is about right. It seems like you get the most miles from full to 3/4 tank. For sure change the air filter when it gets dirty (oil change if needed 3-5k). I just cleaned it since I was shocked how dirty and today I replaced. I am going to take pictures of both and show.. It was really amazing! Cheers.

[914lps]

I can pull mine out clean and replace in 5 to 10 min., at most. I do not replace it after every long drive, I just tap the dirt out and blow the dust etc., out of it with compressed air. I hit it with the air fro the back.

[AzHotLS]

Based on what I've read here my 18.4 - mostly city miles - isn't too bad.

334.2 total miles on 18.1 gallons = 18.4 mpg. Gauge on E and warning light just came on at 333 miles.

Oh, and that's with no AC running as I still haven't got it fixed. But had the AC been running the mpg might have been sucked doen to ~16, then that's not too good.