Lexicon1

Just picked up an 06 SC430 with 75k miles. Pristine condition. Regular Lexus services. Its got Runflat tires and they need to be replaced. All 4 seem to have some inner tire wear.
Here is the question. According to Daizen website, "Oftentimes by 40-50,000 miles, you may begin to see accelerated tire wear, especially on the inside of the front tires.specifically the bushing on the #2 front lower control arms. Over time, the rubber in these bushings goes soft, and causes havoc with the toe settings of the vehicle. Pretty soon the car is wandering and darting all over the road, especially at highway speeds, and you are getting only 6-8,000 miles on a pair of front tires. Simply said - whatever the actual problem may be, make sure you are addressing the correct problem in the correct way." HERE is the question, ...I have no shaking at higher speed, I want to put on new tires and not find out that the new tires start to have abnormal wear........would I be better off just replacing the Lower Control arms #2 as a proactive and just get it out of the way? I dont want to go with polyurethane bushings , too many folks have squeaking problems and I dont want to take a chance...... Ive seen Dorman replacements or would I be better off going with Lower Control Arm OEM from Lexus.
Your comments requested

Yes

The SC430 has higher than normal camber wear. The wheels are slightly tilted, which causes the inner tire to wear more quickly. Most likely, yours has nothing to do with the lower control arm. It happens to all of our cars. If it really bothers you, you can buy a camber correction kit.

iolmaster

iTrader: (1)

I have to disagree with our esteemed mod. I have a 2006 also and it came with the run flats and I had the same issue with inner tire wear. When I replaced the tires in March of 2010 I had the shop put the camber at the minimum and the toe right in the center of the delta. I put Continental DWS on and now have about 21,000 miles on the tires. I rotated the tires about 4 weeks ago and measured the tread depth. They are worn perfectly. 6/32 across all four tires. I rotate them every 5,000 miles and do it myself. So, either I am one lucky SOB (relating to inner tire wear) or we do have the ability to solve the problem. It does not appear that we have to live with this. Just my personal experience.

bacardi

I agree with iolmaster, its all in the alignment. I find the best alignment is,
Front Left -.3
Front Right -.5
Rear Left
Both -.4 Best -.6 Max
Right
Toe= 1/32 each side

iolmaster

iTrader: (1)

-.4 and -.6 is outside spec for the rear Minimum is -.67 degrees I'm not saying it doesn't work though. My rear camber is at -.8.

bacardi

iolmaster
the best i can get mine is .8 rear. my front is .3 and .5
spec.'s for alignment isn't worth sh++.

Yes

I was told by an alignment shop that they could get it close, but they couldn't quite get it to neutral camber. That was before I lowered it. Now that it's lowered, it's not even close.

bacardi

Liquid
The only way to get it were you want it is with a K-MAC Kits, Front and Rear.
Its a one time thing, but not cheap but worth the money.

iolmaster

iTrader: (1)

You don't want neutral camber. Some negative is good. Mine is the same. You can't get to neutral.

scdroptop

iTrader: (1)

Yeah us guys with a drop and aftermarket wheels/tires (especially larger with staggered) have no chance.

I pushed mine to the max at the alignment shop and they weren't even close. I do subscribe to Liquid's summary analysis of the nature of our cars. If you want to go to great lengths to try to correct, then buying an unlimited alignment at shops like NTB for you might be worth chasing. At a certain point in your hunt for excellence sometimes you have to learn just to pick and choose your battle. I have owned over 30 sports cars in my lifetime and I've just realized recently that you can't change (or at least too much) the basic DNA of cars. You can try...but the more you try, the more frustrated you get. Kinda like trying to change your wife...LOL

Back to the OP observation/question: I'd venture to say you have nothing wrong with your control arms or bushings and get your new tires with confidence and get a good alignment (or alignment package as aforementioned) and enjoy that new ride! Post some pics too please!

jzwu

I heard dropping the ride height (reasonably, not low rider type) doesn't necessarily affect alignment. Larger wheels will.

So if I keep the stock 18" wheels but drop 1", the alignment will probably not be affected. Any gurus to chime in?

scdroptop

iTrader: (1)

Well, I can only speak from experience. When I added my 20" staggered wheels, my alignment was way off and I corrected it. A year later, when I added coilovers and dropped my car about 1.5" my alignment was way off and I corrected as best as I could. I was told by several service sources from wheel guys to service guys to coilover mfg and wheel mfg that changing height always alters alignment.

scdroptop

iTrader: (1)

and remember...when you add 19's or 20's to your car you are in essence, "lifting it" a little

bacardi

jzwu
I'm dropping mine .8 front .6 with the Swift Springs that are coming. I still will be able to get the alignment were I want it. If anyone dropped their car really low, K-Mac Kits will let you bring it back to any were you want it. You can bring in enen 3 degree out.

jzwu

I just put in the Toyota TTE sport springs dropping by 1". The wheels are still 18" with the non staggered stock sized tires 245/40-18.

Do I need an alignment? So far the car drives straight just like before the spring change.