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Discussion Starter #1
I have read so much on the front suspension issues for the GS . Unfortunately they have not been correct in many ways in people guessing and not technically knowing how the parts work together.
So here is my take on them.

I have an 03 GS430 with 150 000 KM on it.

Symptoms ,
wandering all over the road.
super light steering at any speed
strong vibration 100km/h and over
front tires howling at 70 km/h
clunking over bumps
clicking when driving or reversing from park (also can be caused by not replacing those small screws on the rotor hubs as they do have a purpose)
rapid tire wear with heavy feathering
some may have bald tires on the inside
Loud howling noise from front end tires
very poor emergency braking
poor gas milage

Fixes
It really starts with 1 as it is the problem that kills all the rest of components.
It is the front caster arm bushings.
When they die your alignment goes to shyt .
The front wheels toe out and the caster goes negative . Causing all of the problems above from one part.
You can replace them with oem's rubber bushings but the suspension geometry is not the best for them and multiplies the pressure. This causes them to fail under hard braking fast as it does not take much. Replace these with urethane and you will be able to go hopefully forever without a repair again.
While you are at it you will have to change the ball joints as well as they will have been stressed by the caster arms unable to take the load and causing the ball joint to be pressed at an angle . They will break and it is not because the ball joints are weak . It is because the suspension is out of alignment and cannot compensate the load of the arms .While you are at it check the tie rods but they can handle the odd angles from the arms.

Once done the car will need to be aligned as well .

You will now have a front end that is rock solid.
If checked properly and nothing else is worn it will no longer wander on the highway .
The tires will wear properly .
The brakes alone is the biggest benefit as it feels like you added a BBK form the amount of grip .
The steering will feel real tight and not over powered . So the thread about unplugging the PS ecu is not needed and the car can be driven properly .
No more clunking over bumps as the ball joint is not taking the bump but the bushing is.
Vibrations gone as the wheels axis is straight and not sticking out which causes the vibrations.
Gas mileage goes up as the wheels are now pointed straight and you are not holding them like a shovel being pushed down the road .

All this from a daizen urethane front control arm kit $100 and a pair of OEM lower ball joints $180 plus alignment $60 .

I love driving my wife's car again and so does she.

I did not install the upper control arm or the lower arm that the ball joint sits on as they are fine and it will tighten up the front end more than i want.
Some people complain about it being to stiff but just doing the caster arm alone is all i needed. I could not care less about wasting the other bushings.

So good luck and stop blaming the ball joints or the power steering as problems when they are not. The cars just need some TLC .

added info.


I also forgot to add my mileage went up by 20% as i am no longer shoveling my wheels down the road.
I was getting 420km per tank and now get 500 (city/hwy) to 600km (more on the hwy) a tank.

With my 70 liter tank
I was getting
420km =16.7 liters per 100km = 14mpg
and now it is
500km =14 liters per 100km = 16mpg
600km =11.7 liters per 100km = 20 mpg

Only other variables are an HKS exhaust and motul 8100 oil until i do a cold air intake and it should be in the 600 range all the time.
 

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^Yup. Agreed 100%.
 

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Discussion Starter #5
daizen does not exist locally , pretty much all from TM engineering in cali.
 

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Only other variables are an HKS exhaust and motul 8100 oil until i do a cold air intake and it should be in the 600 range all the time.
did you have any suspension mods as well? if so what? and how much lower did your car sit after all the mods. great info btw.
 

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Hmm Since Im about to drop new tires on my car and my vehicle is around 180 000km.

I think I just might invest into 2 new LCA #2 just to save myself the hassle down the road.
$125 each sewell price and Im pretty sure I can get em for cheaper locally from my Lexus Dealer.
 

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$125 each? Wow... that's good...

A dealer here was quoting nearly $230 each. :wtf:
 

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Discussion Starter #12
igzy I am glad you have a hood deflector but try to stay on point . If you don't know what caster arms and can' seem to figure it out, might I mention your own adage , try google.
 

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igzy... I believe caster arms are the infamous "Lower Control Arm #2" bars that many of us need bushings for now.

There are two arms on the bottom of the front suspension... a straight bar from the hub to the body of the car (LCA1)... and then another bar (LCA2) that's bent like an S and is closer to the passenger compartment. LCA 2 = Caster Arm

 

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igzy... I believe caster arms are the infamous "Lower Control Arm #2" bars that many of us need bushings for now.

There are two arms on the bottom of the front suspension... a straight bar from the hub to the body of the car (LCA1)... and then another bar (LCA2) that's bent like an S and is closer to the passenger compartment. LCA 2 = Caster Arm
Thanks Crester, I thought so... I replaced mine last fall, I just wanted to confirm...
 

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I know this is an old thread, but I'm starting to wonder if my caster arm bushings are shot.

So I replaced my lower ball joints, end links, and strut dust boots in August of 2013, and while I was at it, I inspected all the other suspension components and all the moving components seemed ok. I did alignment right afterwards.

Fast forward to Spring 2014, and I noticed that my winter tires wore unevenly on the insides, but at the same time, they were on their 4th winter already and close to the end of it's life. So I don't know if this uneven wear happened slowly over the 4 winters, or if it was just from my caster arms wearing out recently. I haven't driven the car much since the spring, so I can't tell if my summer tires are wearing unevenly too.

The only other symptom I've had is the odd clicking/clunking noise, which I've had for several years. I've gone to multiple mechanics to diagnose this, and they all think it is just my calipers, and nothing to do with my suspension.

Is there a surefire way to know if my caster arm bushings are shot? I don't have any of the other symptoms listed in the first post
 

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I know this is an old thread, but I'm starting to wonder if my caster arm bushings are shot.

So I replaced my lower ball joints, end links, and strut dust boots in August of 2013, and while I was at it, I inspected all the other suspension components and all the moving components seemed ok. I did alignment right afterwards.

Fast forward to Spring 2014, and I noticed that my winter tires wore unevenly on the insides, but at the same time, they were on their 4th winter already and close to the end of it's life. So I don't know if this uneven wear happened slowly over the 4 winters, or if it was just from my caster arms wearing out recently. I haven't driven the car much since the spring, so I can't tell if my summer tires are wearing unevenly too.

The only other symptom I've had is the odd clicking/clunking noise, which I've had for several years. I've gone to multiple mechanics to diagnose this, and they all think it is just my calipers, and nothing to do with my suspension.

Is there a surefire way to know if my caster arm bushings are shot? I don't have any of the other symptoms listed in the first post
They are super easy to inspect, but the short answer is yes. Yes because even when brand new they are bad design causing toe out during braking leading to inner tire wear.
Mike
 
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