This is a classic case of where proper diagnosis is essential to avoid the parts cannon. You analyze the tire wear as a starting point then go through the suspension and steering components one by one looking for play using a pry bar, jack, stands, hand cranking, etc. If bad shocks are involved in the wear then its because old shocks stopped damping the oscillation from worn parts in the first place. As I mentioned in a previous post, I agree with Christine that you need to evaluate your steering components with the idler arm being a prime suspect. There are plenty of you tube videos on checking everything but steering is one of the easiest. Jack up one side only and try to create side to side play at the wheel and see what you get. Our 2012 Malibu is the first Chevy I have ever owned that did not need an idler arm by 75.000 miles.
Our 2012 Malibu is the first Chevy I have ever owned that did not need an idler arm by 75.000 miles.
George
Wow George that’s surprising. I have never had to replace one on any of my GM vehicles over the past 40 years. Front ends were religiously checked re-greased with #2 every 3k miles.
Yes. I had all 4 balanced when I got new tires installed.
Originally Posted by christine_208
Did you figure out what a rag joint is?
Yes
Originally Posted by christine_208
You said the center link has greasable fittings? I would think those fittings would only be on the things that are attached to it; e.g. the idler arm.
I didn't check mine. That's what I saw on Rock Auto for mt model Blazer.
Originally Posted by error_401
What wheels (rims) are on that Blazer? OEM ones? Or some aftermarket?
These are the OEM wheels for the 2002 models that have the console shifter (which mine has). They have cosmetic imperfections, but they're still structurally sound.
Originally Posted by error_401
Are the wheels running true? (lateral and vertical, when checking on the rims)
Do you mean is the caster alignment good? I was told that the passenger side caster was maxed out and couldn't be adjusted, but Pepboys assured me that the alignment is good. Here's the diag print out they gave me.
Originally Posted by GeorgeLG
Post a picture of the cupping...
Here's the previous tires I had with the cupping. I still have these A/T tires. I'm currently running H/T tires I bought new.

Inside tread top of image.
Originally Posted by DonL
also, do you have any play I the rear wheels going to the axle? Maybe any signs of fluid arou d where the axle bearing is on either sides?
I didn't check for play, but I can. No signs of fluid. I just changed out the diff oil recently.
Wow George that’s surprising. I have never had to replace one on any of my GM vehicles over the past 40 years. Front ends were religiously checked re-greased with #2 every 3k miles.
My wife mostly drove the Malibu, maybe that's the issue. She drives much more conservatively than I do. LOL.
The angle on those tread wear pictures is not great for seeing the problem. Is it inner or outer tread blocks that are ramped or is it cupping spread across the entire tire surface?
My wife mostly drove the Malibu, maybe that's the issue. LOL.
George
Malibus were nice cars, I remember I had an early eighties one of them with the 3.8 in it. I think the most I ever had to do to that car was valve stem seals. I can still remember finishing up the job and installing clips on the rockers so I could adjusti the valve lash while it was running 🍻
The angle on those tread wear pictures is not great for seeing the problem. Is it inner or outer tread blocks that are ramped or is it cupping spread across the entire tire surface?
George
Sorry for the bad photos. I currently have the tires stored at a remote site.
It's the inside that's cupped. It's not really visible, but you can feel it.
Sorry for the bad photos. I currently have the tires stored at a remote site.
It's the inside that's cupped. It's not really visible, but you can feel it.
Is it every so many tread blocks or are they all kind of ramped?
Yes. I had all 4 balanced when I got new tires installed. Yes I didn't check mine. That's what I saw on Rock Auto for mt model Blazer. These are the OEM wheels for the 2002 models that have the console shifter (which mine has). They have cosmetic imperfections, but they're still structurally sound. Do you mean is the caster alignment good? I was told that the passenger side caster was maxed out and couldn't be adjusted, but Pepboys assured me that the alignment is good. Here's the diag print out they gave me.
Here's the previous tires I had with the cupping. I still have these A/T tires. I'm currently running H/T tires I bought new.

Inside tread top of image.
I didn't check for play, but I can. No signs of fluid. I just changed out the diff oil recently.
I just gotta say, this previous post shows some "Ninja-Level Multi-Quoting" going on!
Sounds like you have systematically eliminated several culprits. But I know I've been tricked several times by where I thought a noise or vibration originated.
It appears to be vehicle speed, not engine speed dependent, which means that it can include all four wheels, the front suspension and steering components, and rear drivetrain.
It just occurred to me that perhaps the mounting bolts for something have come loose? This doesn't seem to fit the resonance behavior you are witnessing. I mention it because I'm running out of suggestions. LOL I once discovered that the bolts to a ball joint had worked themselves loose. It was right after I got the truck and I had a shop do the work for me. (Yet one more event that made me restart doing my own work again.)
I'm liking the suggestion that perhaps there is something going on with the driveshaft or components attached to it. Is the transmission output yoke loose?
I also wanted to ask if perhaps the torque converter was not working correctly. But then you reported that there was that weird tire-wear on the front tires which would suggest that the problems are in the front suspension. Ack! However, it wouldn't be the first time there has been more than one thing going on.
Did you recheck the hubs for any wobble? There should be no detectable free play and the only motion they allow is rotational.
Last edited by christine_208; 08-03-2020 at 11:26 AM.
08-03-2020, 08:57 AM
