Driving north on I-95 doing about 80mph in the left lane. With no warning, my drivers side rear lower control arm sheared off below the bracket which connects to the stabilizer linkage.

Didn't hit a pot hole or anything..

This was extremely scary to say the least, but thankfully I was able to pull over on the left side safely without crashing.

 

What year car?

 

Rust. This is why you check your car out regularly and why state inspections are so common in rust belt states.

 

Looks like 95 model. I bet that sway bar link is shot too.

 

Yep, it's a 95. Haven't disassembled anything yet to check the integrity of the rest of the suspension. I have the lower control arm and the sway bar linkage arriving in the mail today. Hopefully I won't need anything else.

Never seen anything like this before. Like I said, there was absolutely no warning. Basically just lost control of the rear end while driving perfectly straight.

 

Have seen pics over the years with other suspension failures in rust-snow regions. Pretty tough and on cars of this age, check the rest of the suspension as well.

 

The alignment needs checking after it.

 

Obviously..lol

 

Doesn't PA have state vehicle inspections? when was the last time the car was inspected. T his should really have been caught if it's the rust damage i suspect it to be.

 

Car's originally from South Carolina. Came up to Delaware in 2008, and then PA in 2016. I got it inspected March 2016.

PA does require yearly inspections...However there is no rot on the suspension components. I don't think they should fail a car for some surface rust.

I'm going to jack her up later today and see what else I can find.

 

I hope you replaced the other side LCA as well in addition to the sway bar endlink. Chances are its not too far behind.

Can you tell if something had impacted the LCA before it failed, thus weakening it somewhat?

 

I had my daughters 1999 Toyota 4runner over for shock replacement, and found the rear driver side had a swaybar end link broken. It had obviously rusted through, but when I went to look at the other side, I saw some rust but couldn't tell if it had structural problems or not. I replaced them both anyway, but not sure if I had seen it before it had broken if I could tell if there was internal structural problems or not. You pretty much see a lot of rust on any 15+ year old car.

 

And unlike the front lower control arm that is made from what looks like a solid chunk of forged steel, that very thin cross section chunk of pipe that the rear control arm is made from, and is not something that should be found on a top dollar luxury car. And shame on lexus for cutting corners on a suspension part. So what is the material that is above the surface of that tube? Maybe someones lousy attempt to weld it? Or is it just hammered from hitting the other side? No matter what its a very crappy design and bad choice of materials.
On my gen 1's I see too many bad choices with the suspension design at least on these years, I know there where some improvements with the 98 and up.

 

Agreed. Wall thickness is definitely thin on. See attached pic - it almost looks bent. Maybe I hit a pot hole a while ago and it finally gave way. I don't think rust could have caused this. And there is no way someone would weld such an integral piece of the suspension right? Who would do that lol..

Removing this is going to be a real b**** since its broken in half (the whole wheel assembly is free). Unfortunately it's in my driveway so I only have hand tools.

2nd pic check out the rubber on the upper control arm. I can see some exposed metal. Probably will need replacement

 

Yeah possible the upper pivot bushings are on the way out. And notice how those bushing eyes area factory welded on. That is a better picture of the lower arm, and it does have a bunch of rust pitting that could have caused a stress riser that a crack could start at, but still. Why not make it stronger? If you compared those parts to an old 50's chevy these pursuit of perfection parts are very lacking. Now body and paint and rust protection for the body Lexus wins big time. But with power train and suspension component materials and rigidity the old chevy wins. Lexus could have added another 100 or more pounds of stronger materials and better design to the suspension. There is a reason the suspensions do not last long in these cars, it is one of my major gripes about them. That control arm should be a safety recall item, a lot of people could have died if it wasn't for a good driver (you), that is depending on how crowed the road was when it happened. Having an issue at speed with the rear end is the worse thing that can happen. That is why police do that pit maneuver to spin the cars out when chasing them. I've had a front tire blow out years ago the front tire is a better option than the rear to have a problem with .
I'm going to have to check mine out and see if they are similar.