1) Would downsizing to a 16, 17 or 18 inch tires improve the ride quality further?

2) The sun shades, how good are they at blocking out the sun? Would tint still be necessary?

 

1) Yes going to a lower sized rim will result in a smoother ride at a cost to handling. Road noise has more to do with tire brand and size. Going larger rims will net better handling at a cost to ride quality and smoothness. I had a 2006 LS430 with stock 18" wheels and switching to oem 16" lexus rims net me a much smoother ride.

2) Sun shades only block some of the sun and uv rays will still come through and wear down your leather and plastics. It will not help keep your car cooler during the summer. But if you tint your car with the right brand of tint, you can make your interior last much longer and keep your cars interior at least 15f degrees cooler. Shades are more like to help shade your eyes from sun glare.

 

I don't think you can downsize to a 16 because of the brakes on 460. Oem brakes are quite large

 

Thanks for the answers, what's the smallest rim size for a 2008 Lexus 600H L? I went to tirerack but they recommend 18 or 19 inch rims. I then checked out their winter rim recommendation (since winter tires usually have smaller rims) and they again recommended 18 or 19 inch rims for the winter set up. Are 17" rims not available?

 

The car wasn't available with 17s

 

18s are minimum for 600hl and all other 460s

 

im just curious are you experiencing an unpleasant ride in your car why you are considering downsizing the wheels or is it just general knowledge that you wanted to know?