What causes control arm wear?

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I have a 2008 Toyota Camry that I bought with 40k miles in March 2012. In June 2013 I had the passenger lca replaced with oem Toyota lca after putting about 20k miles on it. Less than 18months and 15k miles later the passenger side is due for replacement again. What causes lca bushings to wear so fast?
 
Improper installation? You tighten them when the car is sitting on the ground. The bushing acts like a torsional spring when it gets tightened onto the crossmember. If the car is up in the air by the frame and the LCA's are being tightened then it's gonna overtwist the bushing when it sits on the ground.
 
Hard for me to buy into that. The mounting position for this lca doesnt change. No matter if it is on the ground or in the air.

Edit: not a drop of oil to be found.
 
Last edited:
Originally Posted By: wirelessF
Improper installation? You tighten them when the car is sitting on the ground. The bushing acts like a torsional spring when it gets tightened onto the crossmember. If the car is up in the air by the frame and the LCA's are being tightened then it's gonna overtwist the bushing when it sits on the ground.


+1.
 
Originally Posted By: jsb025
Hard for me to buy into that. The mounting position for this lca doesnt change. No matter if it is on the ground or in the air.


Seriously wirelessF IMO pretty much nailed it.
The bushings don't move vertically or horizontally but they twist. The bushing has an outer shell and an inner core tube with rubber between the two and are bonded together.
They need to be loaded in a neutral position as they are when the car is sitting on its wheels.

When you hit a pot hole the bushing core twist counter clockwise and when you hit a bump it twist clockwise. The amount of movement is minimal and well within the tolerance of the material.
When you tighten it in the air it has to twist far beyond the rubbers rating when lowered on the ground and remains that way, when you hit a bump it twist the rubber even more, so it wont take long to tear the rubber.
 
Originally Posted By: jsb025
Hard for me to buy into that. The mounting position for this lca doesnt change. No matter if it is on the ground or in the air.


When the car is up on jack stands and you tighten the control arm mounting bolts, the bushings are fine as long as you leave the car up on jack stands. But as soon as you lower the car down off the jack stands, you're putting a torsional load on the bushings. If you want your control arm bushings to last, put the car up on ramps and tighten the control arm mounting bolts while the car is resting on its tires.
 
Originally Posted By: wirelessF
Improper installation? You tighten them when the car is sitting on the ground. The bushing acts like a torsional spring when it gets tightened onto the crossmember. If the car is up in the air by the frame and the LCA's are being tightened then it's gonna overtwist the bushing when it sits on the ground.


+2
 
The consensus seems to be that WirelessF is correct and I'm glad to have learned something today.

My question is....What symptoms lead you to change out your lca's? (I think this is low mileage to have such problems)?
 
Originally Posted By: jsb025
Hard for me to buy into that. The mounting position for this lca doesnt change. No matter if it is on the ground or in the air.

Edit: not a drop of oil to be found.


These are tough to install, need to be pretty exact with indexing bolts and washers to get proper alignment, and then torque under load.
 
True enough, 60K on an 08 is a little early for that on a Toyota.
The other possibility is the car was in an accident or has a damaged cradle (IIRC the lower mounts are on the cradle not the sub frame) for some reason or as someone posted they have been subjected to oil or some sort of oil based product.
 
My symptoms are/were tire wear, steering vibration at high speed braking, and clunk over bumps.
 
Originally Posted By: yvon_la
Originally Posted By: wirelessF
Improper installation? You tighten them when the car is sitting on the ground. The bushing acts like a torsional spring when it gets tightened onto the crossmember. If the car is up in the air by the frame and the LCA's are being tightened then it's gonna overtwist the bushing when it sits on the ground.


+2


Mind you, the first lca was changed at 60k miles by the local Toyota dealer with OEM Toyota parts. This part has only been on the car for more like 14 months/15k miles and I noticed the clunk with only 10k miles on the part. I also have no reason to believe the car has been wrecked. It was a one-owner car that was well taken care of.

My symptoms are/were tire wear, steering vibration at high speed braking, and clunk over bumps.

To all of you who say that it was improper installation I am 99.9% sure that this isn't the case. Like I said the factory part and dealer installed parts both wore out in a relatively short period of time and I can't find any information (online or Chilton manual) that says the lca bolts for this vehicle must be torqued with the arm loaded. I think you guys are referring to installation of a different style of control arm.

2001 Cavalier control arm: Makes sense to torque while loaded.
Amazon Cavalier Control Arm

2008 Camry control arm: Tightening bolts without a vehicle load will have no impact. Its simple bolt-on.
Amazon Camry Control Arm

So more specifically, might there be specific driving conditions that could contribute to control arm wear/failure?
 
Which bushing is gone the donut or the rear one? The front style ones can break by just letting the wheels hang while doing other work. This is common on some GM cars.
Is the bar through the rear one free floating or is it bonded to the rubber? I haven't done one of these.

Unless its going off road i cant think of any normal driving situations that would stress them to point of breaking.
At the end of it all it could just be a defective part but it would be nice to find a cause if there is one.
 
Originally Posted By: Trav
Which bushing is gone the donut or the rear one? The front style ones can break by just letting the wheels hang while doing other work. This is common on some GM cars.
Is the bar through the rear one free floating or is it bonded to the rubber? I haven't done one of these.

Unless its going off road i cant think of any normal driving situations that would stress them to point of breaking.
At the end of it all it could just be a defective part but it would be nice to find a cause if there is one.


Technically the donut shaped bushing is toward the rear of the vehicle. This is the one that has cracks and is torn. The bar is bonded to the rubber and does not turn freely.
 
I have an Echo and have had two lcr's replaced but it was because of the lower ball joint which is a part of the lcr. Your sound of clunking is not symptomatic of a ball joint though AFAIK.
 
I wonder if you're parallel parking in the same spot every day and there's some pothole that applies abnormal pressure, beyond what would cause a tire to slip. Your power steering would then be jerking this LCA beyond design.
 
Originally Posted By: jsb025
Mind you, the first lca was changed at 60k miles by the local Toyota dealer with OEM Toyota parts.


If the LCA was replaced at the dealer, the correct way to install that would be to install the LCA loosely while the car is on the two post lift and then take the car over to the four post lift for final tightening of the mounting bolts.
 
I would not trust a dealer to take the time to properly tighten the bolts under load. The almighty flat rate makes it uneconomical.
 
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