An interesting thread. Here in the UK, we don't need to change our tyres for the winter, well, possibly in Scotland but not the rest of the UK. Snow is quite rare, though at present there's a temporary flurry!
My UK spec 2008 GS has come with Yoko Advans on 18inch wheels, which seem quite quiet and well suited to the car despite our pot holed roads.

 

Yo, NGLaser and Rexus300: Nice discussion and one that is very pertinent for folks who roll in the latest-gen GSs. My personal experience with this platform as a tirenerd (development engineer) with Michelin is that Toyota's emphasis with these cars is very much the "iron fist / velvet glove" philosophy (as opposed to the 535i or 550i E60 BMWs with which these cars could be said to compete). I would tend to err on the side of a high-level touring tire (Rexus 300 mentioned moving to Primacy MXV4s, for example). Another alternative (assuming the correct size is available) could be the Pilot MXM4 from Michelin; this tire tends to kick up steering gain a notch, with a bit more pure grip (wet or dry), without much change in the NVH signature (we use this model a lot with our high-end OE clients). If you live in an area with a moderate climate, another terrific solution (I'm kinda hardcore) is the Pilot Sport PS2; these tires are amazingly comfortable given their handling prowess and overall grip level--but you definitely need a "winter" solution for very cold weather or for any dusting of snow/ice. Also, be careful of "plus" sizing with these rides. They're pretty sensitive to unsprung mass (unless you're skilled with shock tuning). Wish I had a new GS460 . . . Chris, with the Michelin Tire Tech Team.

 

Can you tell me what you mean by sensitive to unsprung mass in the plus sizing??

 

Using Yokohama S.Drive UltraHigh Performance Tires. More for summer use, but it never snows here in Southern California. They perform well, look good, and they're pretty cost effective.

 

Thx. Mine is not AWD. However after this reading, I will probably go with the Gran Touring All Season Michelin Primacy MXV4. I will be changing in about 3-5000 miles and will report back.

 

Hey Rexus300: Unsprung mass is essentially the weight of the car not supported by the suspension--wheels, tires, brakes and a certain percentage of the suspension components themselves (that percentage varies with the type of suspension). Increases in unsprung mass can hamper the suspension's ability to respond to inputs (like a steering input, a bump in the road, etc.). Additionally, if you change the rotational moment of inertia of the wheel-tire assembly by a large amount, it can materially affect the braking and accelerating response times for the vehicle (in other words, it takes more effort to "spin up" or "spin down" the wheel-tire assembly). Our amigos over at Tire Rack give a good definition here:
http://www.tirerack.com/tires/tirete....jsp?techid=98

Upsizing adds unsprung mass if you don’t go with a lighter tire and wheel to make up for the larger size and/or adjust the suspension to balance the change. Some cars aren’t as sensitive to a small change; some are (like finely-tuned vehicles such as the GS). Tire Rack gives a detailed explanation about the issue with upsizing and a road test comparing OE and plus size wheels here:
http://www.tirerack.com/winter/tech/...jsp?techid=108

If you’re interested in upsizing or want to check your setup, ask around to find a good, local tuner who can set you up. Tire Rack folks should be able to help, too. Chris—Michelin Tire Tech Team

 

Leaning toward the A/S Plus tires. Any more input on the vibration issue? If this is really
a problem I will go with the Primacy HP's.
Help...

 

I got 18' OEM wheel on 08 GS350 with Sumitomo HTR ZIII which rated as max performance summer on tirerack. I also found some vibration and it increases while the speed starts to go over 80km/h especially on highway when the speed is over 100km/h. Even though the traction is perfect, but the steering wheel feels like it's shaking your hands(get numb after a while). The vibration is kinda annoying when I first change the wheels from 17" to 18". I was worried cuz I thought the vibration was caused by the new wheels.
My original 17" wheels were equiped with Dunlop SP2020 and it's perfectly smooth even over 160km/h.....but the traction is.....
Does someone get Michelin Pilot Sport PS2 or Pirelli PZero nero? Want to hear whether they have the same vibration issue or not.
BTW, does someone have the experience with the new Nitto Invo tires? How do they perform?pro/cons?

 

I am going to say this: Lexus GS is a pretty crappy car when I comes to its ability to tolerate certain tires.

I realize that the 2006 Lexus GS steering rack replacement made the car better with the tires. I recommend continental contipro touring tires as an allseason since it does not TRANSMIT a single road vibe even from grooved highways to older rougher tarmac surface highways. The primacy michelins do it at times since they have a 60,000 mile warranty and possibly a harder rubber thread but much much less than the Pilot Sport A/s with the spinning pattern thread that I really so much disliked.

Now, I could put the pilot sport on my AUdi A8L with 19 inch rim and it would be smooth as butter and would not transmit anything to the steering wheel at all.

In Conclusion, Lexus has designed such a poor lousy steering system ever!! I love my GS since its smooth now with the new steering rack replacement and the primacy has nicely been broken in. I had terrible experience with bridgestone potenza RE 960, Continenal CONTIEXTREME contacts, and pilot sport a/s. Never understood why. I should of got a new set replacement of the orignal continental CONTIPRO contacts instead of going to ultra high peformance all seasons. Thats why I got the Primacy at the end.
I got 4 more months of this car, and I will NOT miss it.

 

interesting....

anyone with 20" rims have any feedback.

My plans are the PS2. Discount suggested the Nitto Invo. The Rim MFG suggested Yokohama S Drive I believe.