Swapping 20" PS4S for 18s...noise, range, ride quality questions

[destructure00]

I have a theory that when it's time to buy new tires for my P3D, I should be able to find a 235/45-18 All Season that meets all of the following:

1. cheaper: I think I can buy 18" wheels with tires, sell my OEM 20s, and be around $500 ahead rather than buying a new set of 20" PS4S. Plus future 18" tire replacements are a little more than half OE PS4S cost.

2. quieter: anyone found anything quieter than PS4S?

3. gets better range: 18" wheel+tire combo should be 5-6 lbs lighter each than stock. Plus more tire sidewall should be more efficient, right? Should I expect to see any measurable efficiency gain?

4. is more comfortable: stock 20s aren't bad, but I'd take a slightly smoother ride over large cracks in pavement if possible

So...anyone swapped 18s to their P3D that can share a good all season tire to look at? P7, PS3, CrossClimate, others?

 

[destructure00]

TL;DR version....is there a 18" tire that's quieter, more efficient, and rides better than the OEM 20" PS4S?

 

[holmgang]

TL;DR version....is there a 18" tire that's quieter, more efficient, and rides better than the OEM 20" PS4S?

i'd expecting any premium-branded grand touring tire to be all of that, over the mhp/uhp ps4s

 

[destructure00]

Efficiency I'd expect, but I'm not so sure about noise. I know a lot of high efficiency tires are super loud due to harder rubber compounds, and that's not a trade off I'm willing to make.

 

[holmgang]

Efficiency I'd expect, but I'm not so sure about noise. I know a lot of high efficiency tires are super loud due to harder rubber compounds, and that's not a trade off I'm willing to make.

you'd imagine grand touring tires are designed with wider temperature envelope, compared to performance ones that require some heat to soften up. so with standard loads and temps -- the "soft" performance tires might very well be very hard.

anyway, if you want 1 measure of noise, browse the european sales website or manufacturer website.
EU laws require labeling of the tire noise - measured external to the car traveling at 80kph.