350AWD

Hello all, I have 2010 GS350 AWD. Tires are Dunlop and have 7000 miles on them and the car has 47k miles. The issue is the rear inner tire are cupping and make roar noise. Car is all stock. I have done alignment twice at the dealer. They are telling me everything is normal. I have personally inspected everything under the car and did not find anything abnormal, no blowing bushing, and no oil coming from struts. I have read there is no camber adjustment in the rear.
What could cause the gs350 AWD this cupping? Only in the rear?
Would camber correct such problem?
Any suggestions would be greatly appreciated.

ibidu1

iTrader: (1)

I have the exact same issue I have yet to solve. Im on an 08 GS350 AWD ive had it on stock tires and staggered 20's both same issue.

Ive replaced rear struts, added aftermarket chamber adjusters, toe arms.

If you find a solution let me know

https://www.clublexus.com/forums/sus...ear-gs350.html

chuckGS350

I used to have an inner tire wear issue when I had my RFT on.
After replaced with conventional tires (Pilot Sport A/S Plus), I don't see the issue anymore.
Knock on wood.
Due for 2 sets in 10K miles. Too bad, they don't make these tires anymore.
I really like them.

350AWD

So it's a possibility that it could be the the tires or get camber bars?

ibidu1

iTrader: (1)

Too me it does seem to be too much negative chamber in the rear. But there has to be a reason why the rear is off on our cars. Maybe its worn out bushing somewhere

350AWD

I checked every bar with a bushing and didn't find anything out of order. When viewing my car from the rear you see both rear wheels are tilted inwards.
I have Dunlop signature tires on it with 10k miles.

ibidu1

iTrader: (1)

Same here my rear wheels have negative chamber aswell. On my next alignment I may have them add 1-2 positive chamber in the rear.

350AWD

Is this something that dealer or alignment shop can fix? By adding few degrees of chamber?

ibidu1

iTrader: (1)

On my car I can adjust rear chamber because I installed aftermarket chamber adjuster shaft. So yes alignment shop can do it.

350AWD

Sounds good, any ideal where I can get a set of the ajustable chamber kit?

This is alive your issue with tire noise and inner cupping?

ibidu1

iTrader: (1)

I run spc rear chamber arms! I have more wear in the inner rear wheel and cupping high and low spots.


http://www.ebay.com/itm/SPC-Performa...1VynNJ&vxp=mtr

350AWD

Latest update to my tire wear and cupping issue for the rear. I ordered the SPC camber bars for the rear. I had it aligned, but I was told this will not correct the tire cupping issue. I was informed that it will only correct the tire wear and that struts are bad that's why it's causing cupping. Tires are Dunlop signature sport. Car has 50k miles on it all stock. I am confused. I don't want to continue to spend money and not receive results. Anyone else have this issue?
Any advice before I buy struts.

Thanks

ibidu1

iTrader: (1)

Most likely rear shocks are good, I was told the same thing and I replaced my rear shocks with no luck and chewed up a new set of tires.

Just last month I had my car realigned but this time I told the tech to adjust the rear chamber so that the wheel sits more vertical so now I have .45 negative chamber in the rear.

So far from handling with the new setup, the car handles way better. I am still keeping an eye on the wear

xbladex00

interesting thread.... I noticed my tires were having uneven wear so i decided to just get new tires... my old tires were bridgestone potenza's.... I had a leak in one of them or something but i just decided to change all the tires since all were about 2/32... I changed my tires to cooper tires RS3 - S or A (cant remember the last letter)
about to do tire rotation in about 1000 miles so hopefully i can give feed back on the un-even wear.... what does cupping look like? Also when they were doing the installation i asked for alignment... I think I saw him align the rear not too sure... Can u really align the rear? the car is all stock

350AWD

Cupping is uneven wear on the tire. It makes the tire wavy and pachy. In other words if you slide your hand down the tire you will not feel it smooth. I can if you google it will explain it to you better lol.