I am still getting used to my recently purchased '01 GS430, and I wanted to bounce an observation of y'all and see what you think.

The car has aftermarket wheels (18" Antera 143s) and low profile tires (don't have exact specs, but I believe 35 series 245 Dunlop SP9000s).

What I am seeing is that the car is very difficult to drive without constantly fighting the steering wheel. It does not drift or pull (I had it aligned just in case), but it seems like every bump, groove, or discountinuity in the road wants to rip the steering wheel out of my hands. It is very responsive to my commands, and I don't detect any looseness in the steering. I am guessing that a large part of this is due to the low profile tires - I certainly saw none of this when I was test driving cars with 16 and 17" wheels.

But this seems to be almost unsafe - I would not dare drive it with only one hand on the wheel, and even with both hands, it seems like I come home with bruised biceps after a long drive.

Would love to get some feedback from those of you with low profile tires, especially the guys (gals) with the 20" wheels - do you see this phenomenon?

Or is there something else wrong here? Maybe more toe-in is recommended with lower profile tires?

Leon

 

sounds like trammeling. you are also probably feeling the lower profile, wider tires too.
also, maybe you need ball joints.

I have 245-40-18s and I don't get what you describe. I do have the car follow grooves or ridges in the road sometimes, but much milder than the way you describe it.

the GS in general, even stock, does transfer more road feel & vibrations through the steering than any other Lexus I've driven.

 

I run 18's on my car with 245/40 F and 275/35R with dunlop sp9000's. I don't have any problems in the wheel feedback going over bumps and uneven surfaces. About the only time I feel the wheel wants to go left or right is when I'm approaching a stop (from about 10mph ) and the road is extremely buckled and uneven. If you have the sp9000's , check your tire pressure. I've found the dunlops get a bit squirrelly if the psi is below 38. 40psi seems to work best .

 

I have the exact same problem that all of you are having. Im runnin 245/35/19 275/30/19 and I had no problems before running the stock whens. It cannot be the ball joints or lcas because I replaced the Lower Control Arms to cure the tramlining problem when I first bought the car. I guess its just part of life when ur rolling on some nice big rims

 

I have it too...on stock 17s.

I changed tires two months ago, and it seemed to me to go away for a while. I will check the tire pressure, fix it if necessary and update this post.

 

I'm running 19's and I don't have that problem either, only on some serius imperfections. I can actually drive with no hands (not recommended) and bumps still don't unsettle the steering. Hope you find out the problem.

 

Part of it IS the reduced sidewall and getting used to it. By the way 245/35/18 is too small. You should be running 245/40/18 to be at OEM size. This also gives you more rubber for a more compliant ride.

 

Hi Leon,
I am running stocker 17" with Fuzion Zri 235/45/17 @ 32 psi and have the very same problem. I have a 2001 GS430 CPO car with 65K miles and recently took it to the dealership complaining about this issue. After about a week all they ended up doing is verifiying the alignment and set the toe which initially My questions would be how many miles do you have on the car?

My next step is to take back to a reputable suspension place here in San Diego and have the check the bushings to make sure they are in good shape, beyond that I am at a loss.

Good luck.....

House

 

Can you elaborate on what trammeling is? I did a quick search and found a Mustang forum with a guy describing an identical problem to mine after installing bigger wheels - but I didn't see a solution:

http://www.superstallions.com/forum/tm.asp?m=14786

How does one fix trammeling?

 

I think this is the same setup as mine (245/40/18). I'll check the pressure just in case.

I wonder also if the offset of the wheel makes a difference? My Anteras seem to have lots of negative offset, with the tire being almost flush with the outside of the wheelwell. Could that be a contributor? How is your wheel/tire centered in the wheelwell (in/out direction)?

 

I also doubt that it's caused by worn/loose components - first, it only has 37,000 miles; second, it seems very responsive to my commands, with no slop; and third, I took it to a very reputable alignment shop, first thing they do is check for loose or worn components.

So you just learned to live with this? I am literally afraid to let someone else drive it without giving them a "speech" about this behavior .

 

Yes, I'd be curious what you find...

 

I hope so too . Not that I want to drive with no hands, but at least I don't want to keep fighting it with BOTH...

 

Yeah, I think they are 245/40/18 (I'll check tonight).

I guess one option I have is to try to find a tire/wheel shop that would be willing to set me up with a set of factory-like combo for a test drive, and see what happens. Then I can take it from there - although I do love the look of the big Anteras...

 

Wow, so even with 17's you see the same problem... I have 37,000 miles on mine - hopefully too early for suspension to be worn out.