'14 Brembo 5.0, 100% bone stock.

So, the last couple mornings the temps have been around -12F, with windchills close to -30F. I've started the car and let it warm up for 15-20 minutes before going to work.

Yesterday as I slowly backed out of my driveway, I turned the wheel full lock to go around the garbage can at the end of the driveway and I got a rhythmic bang/clunk from the front end as the tires went around, bang-bang, bang-bang. Suspension was probably still fairly cold at this point. By the time I got to work an hour later (car drives 100% fine all the way to work), I tried replicating it in the parking ramp and the car didn't do it and was quiet and smooth at full lock, like normal. I know these cars don't hit the tie rods or whatever at full lock.

It was basically like what would happen if you had a ton of ice built up behind the front wheels, then turned the wheel and the tire was stuttering up against that, but there is no ice behind the wheels.

I tested it again this morning, and I got the same bang with the wheels turned both ways, full lock, backing out slowly. Again could not replicate in the parking ramp.

Any idea what this is? I've turned the wheels full lock and peered into the wheel wells with a flashlight and clearance looks fine everywhere.

The only thing I can think is that Friday night I took the car to a coin car wash and flushed the undercarriage for a good 10 minutes, then ran the car through a touchless car wash and then parked it at home outside. I did park the car in the heated garage for a couple hours right after to wash the wheels nice, but then it was back outside, likely before everything underneath dried up, so maybe there's some frozen ice under the car on the suspension pieces? But I would think then that maybe I would've had this bang just the first time as I cracked the ice off of whatever suspension pieces. I also don't see any ice on any of the suspension components when looking in the wheel wells with the wheels at full lock, everything looks perfectly normal. Doesn't seem right it does it in the morning, but then not again later on. Or are my all season tires just that frozen/rock hard in the morning that they are actually slipping/stuttering across the driveway or something?

I didn't notice if it was doing this prior to the wash the other night, as I typically don't turn full lock to get out of the driveway, so it could just be a coincidence that it happened after the wash and in the extreme cold.

 

Chances are it was just the temperature that caused it. Expose metal to -12F temperatures for a couple of hours and will get REALLY cold. All sorts of sounds would come from my car when I went to school in Upstate New York during the winter. As the car would warm up though the sounds would subside and everything would return to normal.

 

This sounds reasonable. When it's cold, I get cowl shake and rattle even with the top up. It's disconcerting, but it rarely happens in nice weather.

 

Mine does exactly the same thing but at temperatures in the upper 20's to low 30's...don't know about anything lower than that since I park it during the winter months. My deduction was it's the hydro-bushings on the front lower control arms.


John

 

Arent the front control arms known to fail prematurely. I might be wrong but I thought I heard about a TSB for them.

 

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Yes, there are several threads for this TSB. But what you are describing is for HEAT. The FoMoCo fix is new shields for the front Lower Control Arms. The OP's message is about COLD. So I think it is different.

 

Our cars do not have an upper control arm in the front. The S197 cars only utilize a front lower control arm.

You are correct. There is a TSB for an updated control arm with a different Hydro bushing and heat shields.

 

Thanks guys, I think I'll just see what happens when it's warmer out. Guessing it's probably just the cold but I'll just have to see, might throw the car in the heated garage for the day on Saturday while my wife is at work and then see how it is.

 

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Oops, my bad, I updated it to 'Lower'.