bx167

Hi, I have 99 RX
Currently, I'm using the premium gas and only get 250 miles for every fill up.

I drive 70% highway and 30% city. Mostly 75 - 80 mph on highway.

Can I have some suggestion on better MPG?

Daddy-O said he runs 350- 360 on 17-18 gal. How did u do it?

Thanks in advance.

cephraim

I tried two tanks of 92 Octane for the first time.
Am getting about 1.5mpg more than with 87 Octane.

I understand that the better air filter (B&N?) can help, too...

Shonuff

daddy-o has a bigger tank than you. you have a 99 he has an 02? they added an extra 4+ gallons (more or less) to the tank of the newer models.

bx167

Is it normal to have 250 miles on 15 gal?

Is there anyway to get better?

Oh...also

For having air-conditioning on all the time, does it affect the gas milage?

Thanks

EnzoRX

bx167

I get about 16 to 18 mpg (according to the info supplied by the RX300 computer). I drive mostly city traffic. My 2001 RX300 has the bigger 19.8 gallon tank though. I usually get almost 300 miles on a tankful of premium unleaded (we only get 91 octane here in California). I know that when I set the cruise control at 80 to 90 mph on the freeway...sometimes that drops to 14 mpg depending on if I'm going uphill or passing people.

I believe that using the air conditioner does cut into yer gas mileage. I don't know how adversely it affects it though. I could guess that it would cost you another 1 mpg more if you have yer a/c blasting away.

I guess if we both didn't have such a lead foot, our mpg's would improve. Cruising at closer to 55 to 65 mph would probably improve our mpg's.

malhokc

250 miles on one tank sounds about right for the 99-00 models. I'm averaging about 18 miles/galllon with 75%/25% Hwy/City driving. The size of gas tanks are bigger for the 01-02 models. I've been happy with the 87octane.

bx167

So it's ok to run on 87 octane? and still get ~250 miles?

Oh...it's pretty good.

Anyone notice any MPG difference between 91 octane and 87 octane? What about performance?

Daddy-O

There you go!

My K&N filter has added 8% to my overall mileage and I use cruise control like it was a religion...but it's mostly your right foot that has the most effect on mileage.

For more threads ons on the K&N:
https://www.clublexus.com/forums/sea...der=descending

For more threads ons on the mileage:
https://www.clublexus.com/forums/sea...der=descending

cephraim

Yes, as I said above, I noticed about 1-2mpg difference.

salimshah

Change the display to mpg [NOT AVG] and monitor the co-relation between your driving habits and the gauge [Safety first].

Some months back, a member came up with an imperical mpg formula.

Salim

Handogen

87 octane? Come on guys... you own a Lexus... spoil your baby as she spoils you!

I have a 99 RX and I believe the gas tank is something like 17.2 or 17.4 capacity... They enlarged the gas tank in 2001+... bastardos (I'm not jealous). I also get to about 250miles before I fill up... but at that point I'm usually only putting in 15 gallons before it's full. I'm sure I could drive another 40 or 50 miles before filling up if I wanted to. But running out of gas sucks.

I installed the K&N high flow air filter and it seems to have improved things a little.... honestly it's marginal because this Lexus engine is already finely tuned. My opinion is get it if you have an extra $50 to spend... because it really is marginal. Personally I like experimenting and trying different mods. I want to get the most out of my Lexus experience.... who doesn't?

Something we need to remember is The RX300 is the lightest vehicle in its' class.... and in my opinion, the sportiest V6 SUV I have EVER driven. I used to have a Jeep Grand Cherokee Limited that chugged along at 14mpg city and if I was lucky, 18mpg highway. If you've driven SUV's before and forgotten how sluggish they are, go drive a straight 6 Jeep GC (4.0 liter and still a slug!!!!). I can drive my RX300 without care now because even with a lead foot, there's no way I average below 18.2mpg.

Enjoy,
Hando

cephraim

If it runs fine on 87, what's the sense of "spoling" my RX?
Seems like you're throwing away cash with no benefit.
On the otherhand, I have been told in the past that putting in a tank of high-octane every now and then causes the engine to "burn hotter", thereby cleaning the pistons/valves a little.

So, I run 87 for 3-4 tanks, then 92 for one tank.

The 1-2 mpg difference does not cover the price differential.

gcrim21

cephraim,
Please elaborate on a 'R&N' air filter please. I'm not familiar with that name, brand, etc..

gcrim21

Handogen

I believe in spoiling my baby and giving her the best. What's the sense in putting cheaper gas to save a couple dollars a month? I run the 91 because it burns cleaner, it's good for my engine, and it performs better.

But to each his own....

Hando

cephraim

Sorry, I guess it's K&N.

Handogen:
re: gas
I'm curious about the "burns cleaner" comment.
Is this true? I know it burns hotter and can clean existing soot off, but does it produce less soot?

Thanks