Hey guys, just picked up an 04 ls430 custom luxury, premium package with 18" stock rims. Pictures will be coming but it rained today after work and it totally ruined the photo shoot.

A couple of questions.

Do the stock 18s only come on the euro-tuned sport suspension?

What psi are others using on 245 45's tires? Mine are nokian wr's with a max pressure of 51 psi I believe. I went to add air because they looked low but it turned out they were sitting at around 39psi. I dropped it down to the door recommendation of 33 psi and man they look really low now.

Anyways, good to be in a lexus. So far an awesome car, pretty much what I'd expect from Toyota after owning 9 of them.

 

congrats, I usually put around 40-45psi... If you have 18's, you should have sport suspension. What color combo did you get.

 

I'm pretty sure the 18" were a standalone option, you can have the 18" without having the sports suspension. But, having the sports suspension does mean you will have 18" wheels.

Go figure that out logically...

 

Color is mercury metallic with black interior. 40-45, that explains why the recommended 33psi seems so low.

 

Wow, Ive got 35psi in my 245/45/R18v's and I thought it was a lot. I had no idea you could put 40-45psi in a tire. Is the ride different especially with air suspension?

 

Just checked and my tires max pressure is 44psi. As I said I'm at 35psi now. How high can I safely go allowing for summer heating? What negatives/positives are inherent in overinflating?

 

You are 100% correct. The 18s were a standalone option, which means all cars can have it, but it is standard with the sport suspension package.

From my observations, most 04' don't have that standalone option, you only see the 18s on the sport on a 04'. 05' and 06', Lexus start putting it on most cars, it is rare to find a 05'/06' with the 17s.

 

As for tire pressure, I usually stay somewhere between 36~40 psi for optimum tire wear.

The recommended tire pressure is almost always too low.

 

As long as you don't go over the rated max pressure, you are fine.

I always use the pressure that gives the most even tire wear, in my opinion, on the LS430, 33 is under inflated, 40+ is over inflated.

Other then tire wear, in general, higher pressure make the ride stiffer but gives you better gas mileage.

 

Exactly, over-inflation balds your tires at the middle. The "positive" of over-inflating is that you get less surface contact and so less resistence, which leads to slightly better fuel economy. The negatives far exceed the pluses though:

1. the over inflation increases fuel efficiency as noted above, but then reduced your road grip as well around corners, so it's a double edged sword.

2. you are prematurely balding your tires, which depending on the type of tires, you're paying for a tire earlier which could offset the savings in fuel.

3. more likelihood of a blowout from hitting objects or potholes.

Anyway, with 18", I think max. for overall "efficiency" and savings would be about 40 psi. no more. With my 17" I run them at 35, although recommended 33.

 

Just bumped them up to 42psi, safe since max is 51, seems to ride pretty decent. Might try the chalk test tomorrow to see how even they are sitting.

 

Took some pics after I polished her up.

 

Very clean!

 

WOW, good looking automobile. Have lotsa of safe and enjoyable miles in her.

 

congrats, very nice.

for tire pressure i was told to inflate to around 10lbs below the tire max, this may only apply to stocks. i cant speak for those running stretched.