When I bought my new 2021 ES 350 a month or so ago, I really wanted one with 18” wheels—-look a lot nicer to me and I like with brighter, rather than gray color, look. But to find a car with them, I had to accept a lot of other costly options I didn’t want and didn’t want to spend for. So I’m thinking of changing out the wheels and tires for 18” Lexus OEM ones (preferably those noise reduction beauties) either now or when the first set of tires need replaced.
Hesitant to buy used through E-bay for fear of problems (bent wheel or some thing). I imagine I’ll get dealer price on new ones then check with Tire Rack, etc., then sell my old ones on E-Bay.
I assume it’s simply a matter of substitution. No other changes or alterations to the car are required, right? I also assume the smoothness and quiet of my car’s ride won’t be noticeably compromised. Hope the answers are all yes!

 

Read the owners manual. Mine says that cars with 17" can not go up due to different suspension geometry

 

Whew! Thanks for saving me from a blunder! Will let it go.

 

I'm pretty sure you'll be fine. There's enough room to fit a bus under the wheel wells.

Worst case scenario, you can get an 18" spec alignment assuming there's one specified. If someone can post the alignment specs from TIS for 17 and 18" models that would help clear this up. I forgot to look during when I had my subscription.

At most what the manual is stating is that that the camber or toe angle of the 18" models vs the 17" models may cause for some rubbing of the plastic fender liners in maximum load and maximum angle situations (basically super rare) if at all. Even then I assume they're just being extra careful with the precaution. I can't imagine the camber angle of the 18" model being that drastically different than the 17" model on what's essentially a grandpa's car. Something here isn't adding up. I may spend the $20 to get another two day subscription just to see what's going on. Hitting self on head for not looking this up when I had the chance

Also the overall diameter of 17, 18, and 19" tires are essentially identical but for 0.1mm (nothing basically)

 

For the differences between 17 and 18" tires you're correct the difference is in the tenths of mm range; however, for 19" tires the difference is in the 2 mm bracket [a tad less for 18" and tad more for 17"]. For specific numerical differences comparisons between 17" and 18" or 19" tire size changes, TacomaWorld has a tire size calculator which makes it very easy to compare differences between tire sizes. The following are links for the calculations for ES 350 recommended tire sizes:

215/55R17 vs. 235/45R18 tires

215/55R17 vs. 235/40R19 tires

Also, per the Lexus ES350 Owner's Manual dimensions and weight table [ on page 382 in the 2019 version] the tread [track width would probably be a better item title] of the 17" tire size factory equipped vehicles is 0.3 in.(10 mm) wider than the 18 and 19" tire size vehicles.

On navigation equipped vehicles, there's also this "Limitations of the navigation system" item (on page 111 of the 2019 LEXUS ES 350 Navigation and Multimedia System Owner's Manual):

There is a "Tire change calibration" procedure/function (on page 104 in the 2019 version) that "will adjust miscalculation caused by the circumference difference between the old and new tires."

You would have to know the fine details of the navigation firmware to how "set in concrete" sensitivity to a specific tire size is. Highly doubtful that there's separate firmware loads for each factory configured tire size but what the firmware looks for to determine factory built tire size and how accessible it is to non-Lexus authorized people is unknown.

 

Thank you all. You guys are learned and real gentlemen.
I’ll now shop wheel prices and take it from there. Your time and effort are sincerely appreciated.

 

I think that there are two separate issues at play here, and I think that some of the replies here are mixing them together.

The first issue is how a change in the diameter of tires will have an effect on the accuracy of the speedometer, odometer, navigation system, etc. The other issue is about the way that different wheel sizes come from the factory with different suspension geometry.

Again, those are two separate issues.