Yeah I saw that. His conclusion is faulty. It makes little difference. The new ones might do the same thing. They still use nylon in tires, and so brand new tires can have flat spots that thump when they've been sitting in the cold. All he needs to do is read the sidewall, where the construction is described in detail. And obviously phenomenon has nothing to do with the age of the tires.

I'm not saying it's the tires. I'm saying it could be. Nothing posted has eliminated the possibility.

 

sounds like a strut issue.

 

Just a quick update, FWIW.

If it was a nylon tire issue, then the "thump" would have been there since tires new in 2016 and plenty of subfreezing temps every winter here in lovely Dayton Ohio area. The HHR is parked outside on the driveway 24/7 and has been my daily driver and snow and salt car since 2011. I've owned many cars with nylon tires, and the thumping noise is not that kind of a thumping noise. It's a noise I really can't ignore, IMHO.

Struts? The HHR has plenty of suspension creaks and groans these days, but a strut seems unlikely because of the obvious rotational frequency aspect of the thumping. Although, struts have crossed my mind.

Cleaning and lubing that rear brake caliper didn't change anything; the slide pin had plenty of lubrication and was not rusted, binding or frozen. Red paint simply peeling after 6 years and 23,000 miles. As many of you know, salt in the rust belt REALLY does a job on cars.

Not making any progress to date. Sound still sounds like it's coming from the front. Given the weather is starting to warm up, the thumping should be gone until next winter or until a total failure of whatever component is making the noise. I only use the HHR for local trips and no longer have to drive it to work since I retired.

Anyway, that's my story, and I'm sticking to it...

Ron

P.S. I do appreciate everybody's comments as I always have on this forum.

 

Yeah, nylon tire thump is most noticeable on smooth pavement.

If you hear the thump when you hit a bump, I would have guessed a strut. I experienced that once. Only did it for the 1st 1/2 mile or so. Not my car. It had recently been outfitted with low-cost generic shocks. My guess was there was something wrong with the valving and the dampener had to prime itself or something. Glad I didn't have to deal with it.



But if it matches the tire rotation frequency, pretty much has to be something between the output shaft and the pavement, doesn't it? Guess I got nuthin. Except I once had such a thump that was loose lug nuts.