feldman

I replaced my 18s with 17s on my 2005 LS430. The ride is better, and the steering is lighter. Also the steering wheel doesn't turn in the direction of the road slope when stopping, which it does with 18s. The gas mileage is about 1mpg better in the city. I keep the front tires at 38psi cold.

The handling is worse however. The 18s are outstanding around the corners. So it is advised that you test drive a car with 17s before you make the switch, because you might not like the handling with 17s.

It is my understanding that the LS430 was designed for 16s, and Lexus decided that appearance was very important to many buyers, so they changed the wheels in '03 to 17s and provided for an 18" option. I believe you can attribute all differences in ride to wheel size because other than the transmission change in 2004 and the slight changes to the lights, it doesn't appear that anything else of significance really changed in the period 2001-2006.

At their 800 number, Lexus indicates that they advise against changing wheels, however the dealers do it all the time. It is unclear why Lexus advises against it, they have never provided a reasonable answer. The odometer is not affected, so long as you use the correct tires (225/55/17, for example).

As you drive the car over a period of months, you will get used to the ride and you will probably like it more. It does have a very different feel from other Lexus automobiles, especially in its steering.

rjfiore1

Hi Feldman
Did you use lexus rims or aftermarket? How did you handle the tire pressure monitors? Was it easy? And lastly, do you find the ride MUCH better (easier over bumps and less noise in the cabin) or just ok? Thanks for your input regardless, it's helping me to better make a decision. I don not need to go 100 mph around a turn..... IMHO, the car is not for that. I would have bought a Porchse

rjfiore1

Thanks for the info. Good advice!!

19psi

if all you are interested in is the ride, i would definitely go with the 17" wheels and higher profile tires. the size of the tire makes all the difference in ride and handling. your handling will suffer, even transient response while changing lanes on the freeway, but it own't be too bad with 17's.
let me recommend kumho solus tires as a very nice smooth quiet tire for those 17's as well.

feldman

Hi rjfiore1. The 2005 LS430 does not have pressure monitors in the wheels, so that's not a problem.

I used lexus 17" 6 spoke rims.

The ride is smoother. My wife noticed the difference immediately, she said it drove more like my LS400 (which is on 16s). I personally don't believe that there is a huge difference in the noise level. As you know, because the LS430 is an extremely quiet car, it appears that the road noise is significant, even though the overall decibal level is very, very low.

I think that you have to try a car with 17s yourself to be able to see if you find that there is a difference. For me, the difference is significant, especially in the force required to turn the wheel, but you may see things differently. The ride at 33psi is much more compliant, but I'm running these tires at 38psi to make turning the wheel easier, so the ride is slightly harsher than at 33psi, but not as harsh as on the 18s.

I agree with the previous poster that the age of the tire does make a difference. If you have an '05 as I do, for example, it's not too tough to find an '05 with 17s, comparable mileage, and the original tires (to make a reasonable comparison).

Having said all of this, the overwhelming majority of people that I have spoken to prefer 18s. For most, the appearance of the car is substantially more important than the compliance of the ride, and most people seem to think that the car looks better on 18s.

rjfiore1

Thanks again for your advice feldman. You bring up really great points and advice. I agree that most of the people here will prefer the 18's and the look compared with the 17's- looks much more youthful as I am sure that many of the younger owners that are fortunate to have such a nice (and expensive) vehicle. I feel fortunate to have one as well!!! I am going to find a 2005 with 17's though to compare.

lexusthai

This is what's written at http://www.thetruthaboutcars.com/reviews/lexus-gx470

"........The 470 is also perfectly screwed together, ridiculously quiet at cruising speeds and absurdly easy to steer and brake. No, the problem that keeps the GX470 from being a "true" Lexus is its ride quality, or lack thereof.

The GX470 has a body-on-frame chassis and live rear axle. This mechanically robust set-up is ideal for SUV drivers determined to tackle the rough stuff. In terms of upmarket 'soft roaders', it's positively barbaric. And no wonder. Even with its adaptive variable suspension in full comfort mode, the GX470 makes you feel every lump, bump and jump. A buckboard with wooden wheels would be worse, but only just......."

If you could feel every lump, bump and jump in the GX, and you think that your 04 GX had a better ride quality than your 05 LS430, I believe there's something wrong with more than just your tires. The bushings? Other suspension components? It could be as simple as your tires being overinflated. Old 2004 tires? but before you go change your tires, have the suspension componentd thoroughly inspected. I live in NY/NJ area with potholes and I still consider that my LS rides way better than the 2003 MB E320. I don't have the 18 inch, only 17, but it couldn't make that much different.

I wish you live in the NJ/NY area, I have the 17 inches and I'd been wanting to try the 18 inches. We could swap for a while. Do we have LS meet in the East Coast?

jaymk

I had Dunlop Sport and changed it to Michellin Pilot Sport A/S.
It rides super. I usually drive it on Sport Mode and love the handling. Yes I agree there is a litlle road noise but thats it. The car drives very tight I mean its sharp and crisp . I was thinking to have the Bridgeston Turanza but decided on the Sport A/S.
If possible drive one with it and see how you like it.
Thankyou