Tee

You need to replace the left rear control arm like others an myself have in this thread and it will solve the wear issue. If the dealer is not working with you, you have three choices..

1. Go to a different Lexus dealer that will work with you.
2. Call corporate in Cali to report this issue with customer servive to get some movement under CPO if it is corvered (IDK).
3. Buy the left rear control arm yourself and get installed.

nkoppy

Thanks, ancdmd.

So if the control arm itself isn't bent, rusted or damaged in some other way, it doesn't sound like replacing THAT rod would do much to solve the problem? (i.e., maybe if there are worn bushings it could get things back into proper alignment in the rear suspension?)

Very helpful. Thanks again!

Best,
-Nick

ancdmd

As Tee pointed out, the control arm is likely suspect. True, it's not the metal components such as the actual control arm or rod that is worn, but rather the bushings installed in them. Check all the rubber in the rear suspension and replace whatever is worn; usually to replace the rubber components you have to purchase the entire part assembly such as the control arm or the rod.

nkoppy

Thank you, Tee.

I noticed in threads on this issue, that Lexus offers 3 different lengths of the control arm, to achieve differing rates of camber adjustment. If the bushings all check out, then maybe this is what I'll have to do. Thanks for the reply. I'm on my way to the dealership very soon, and we'll see what they say. I'll post an update. Thanks!

Best,
-Nick

HiloDB1

iTrader: (3)

Nick,

You could also contact FIGS on this forum as he makes adjustable lower control arms for our cars. He may have a set thats available. These do not have rubber bushing in them but spherical heim joints. So they will not wear over time. They are adjustable so you can dial in your suspension vs the stock arms which only give you set adjustments by replacing the arms.

MDSC

iTrader: (3)

most likely if your car is a non air suspension the springs are sagging over time and the car is slightly lowering itself therefor your camber is going more negative. Figs makes great product i actually was not aware that they made arms for our cars. I ended up installing megan camber arms on my wifes car. I know some people have said that megan has questionable quality on their arms but i havent had an issue besided the adjusting nut isnt stainless or coated so its showing surface rust. Other then that megan arms have rubber bushings on both ends. Sure the spherical ends will last longer but i still like the car to ride as smooth as possible.

nkoppy

HiloDB1 and MDSC -

Thanks for the info. The Lexus dealership just called and said that when they put the car up on THEIR alignment rack, they showed the rears were (just barely) within spec. (at -1.8 and -1.9). They didn't do anything to adjust the camber to get those readings - that's how it was when they drove the car onto their rack. I asked them to look hard at the bushings, springs, struts, etc... and search for anything that is worn out or broken. They found NOTHING and said there is no repair required at this time. I'm feeling a mixture of relief and confusion at the moment...

Even IF the alignment is truly within spec, it doesn't explain why the OE tires prematurely wore out so quickly and in the very abnormal (inside edges of the tread first) way that they did. There was still 12-15k worth of tread left across the center and outside edges of the contact patch on all 4.

I'm really going to watch this like a hawk now with the new tires, and if I start to see signs of this kind of wear again, I'm probably going to get a set of those adjutable control arms, since the rear camber is right on the edge of "acceptable limits" right now.

How the tire shop could show -2.5 on theft rear 2 days ago is a mystery to me. I'm not going to call them incompetent - they helped me get almost 40k miles out of a set of 25k sport tires on my old GS 430, by keeping them rotated, balanced, and the alignment in spec over the 5 years I owned it. So, I really believe that they know what they're doing. I'm wondering if they have the wrong "Mfgr's. Specs" loaded into the computer on their alignment rack??

I will get a printout from the Lexus dealer when I pick the car up today and bring it in to the tire shop and we'll compare what each party claims to be the baseline numbers for the '05 LS with 18's and standard suspension. Maybe that will provide some answers.

Thanks again to everyone for the tips and great info! I'll let you know how things progress...

Best,
-Nick

waijai

iTrader: (9)

Was there any noticeable temperature difference between one day and the other? Tire pressure can affect alignment.

Also, as a car moves, the camber/toe settings can change dynamically as the suspension goes through its range. Yes your car at a static height may show to be within spec, but while moving it may go through additional stroke as your suspension ages. Additional compression from worn suspension = lower = additional negative camber.

ancdmd

Another thing to consider is your tire pressures. With the inherent negative camber, any under-inflation will cause exaggerated inner tread wear. The center of the tread of the tire will not wear much at all since with under-inflation the center of the tread has much less contact with the road.

I have 20" wheels and 275 tires in back, and went right through the inner edge of the left rear tire in no time due to under-inflation. A few lbs of air pressure makes a huge difference. I am now running at least 45lbs in the rears and 47lbs in my front tires. With 17" or 18" wheels you don't run that much pressure but still you may need to be running 35-37 lbs or maybe even more. If you've only been running 30-32lbs and you fail to check the pressure once a month odds are you've been realistically running around with much less pressure for most of the time.