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Discussion Starter · #1 ·
Hi guys, 2020 Challenger Redeye Widebody, 5400 miles. Took it in because it does something pretty weird. If I drive it first thing in the morning, when the car has been cool all night, I get a steering wheel shimmy (like unbalanced tires) at 70 mph for about 3-5 minutes. Once the car warms up, it completely goes away. I know, weird. Took the car in, they rotated the tires and balanced them using the procedure detailed in a bunch of threads here. No help. Took the car back, the dealer said they though one of the tires had a bad belt, got 4 new tires under warranty...no help. While the car was in, they found the supercharger was "bad", they replaced it under warranty. When they tested the car with the new tires, the tech said he felt a vibration that's coming from the driveshaft, so we are waiting for a new driveshaft now.

If it was a balance issue, you would think it would not go away once we have temperature. This morning it was around 44F here in Dallas, took the car out and it did the shake for 4 minutes, then it went away. I am using the same exact freeway entrance for all these tests. I went down about 5 miles, turned around and went up the same entrance, no vibration. Parked the car for 5 hours, it cooled off, got on the freeway again, no vibration.

If I put the car in Track mode, the vibration is not as violent, but I think that mode stiffens the steering anyway. Could this be a suspension problem?

Any suggestions? Thank you.
 

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I get this too. Its flat spots in the tires. Pretty normal. After a while the tires warm up and get more pliable. This is a problem with the mustangs too, and they use the PZeros. They are rock hard in the cold. Mine does the same when its been sitting for a day or two on my cold garage floor.

Tire flat spots, get different tires or ignore it.
 

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Tires are square from the cold?

"Once the car warms up" does that mean via driving or sitting still in the driveway?

If it is from driving the car, then the tires are thoroughly warmed up and have regained their normal shape.

Oh, if you have PZeros, yes, get rid of them ASAP.
 

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The C6 vettes did this too. They also had rock hard GY runflats. Cars like ours sit more often than not and cold tires on cold garage slabs get temporary flat spots. Vette guys buy big chunks of rubber and lay them down and park on them during the winter to prevent bad flat spots. Lets the tire sink in and not deform on a hard surface.
 

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had this issue for a while, it’s driving me nuts. I took the car to the dealer and they found nothing and told me to replace my tires.. sometimes it goes away. Sometimes its unbearable. I honestly think it’s a semi frozen caliper
 

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Air your tires up to 50 psi cold. Then the next morning if it still does it, it's not the tires.


Sent from my SM-N960U using Tapatalk
 

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Discussion Starter · #7 ·
Really appreciate the help. I don't like the tires anyway, so I'll get Michelins 4S all around. I can tell you this doesn't happen with my GT500 and it has Michelins, so I see what you guys are saying.

I'll do the 50psi test just in case, thank you everyone.
 

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I leave crappy 15" BF Goodrich's parked on cold concrete for 5 months in the winter and they don't flat spot, are these tires really doing that?
Yeah I've gotten flat spots when it sits but it goes away when they warm up.

And it's the reason Brampton inflates the tires to max sidewall pressure before shipping.


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For those you who get this, are you on pirellis a/s or summers?

Also do flat spots really happen in a day or 2? I find that crazy, but who knows. I get some shake as well, but fully intended to replace the tires ASAP from the get go. Just trying to figure out what tires don't shake and flat spot so fast.
 

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For those you who get this, are you on pirellis a/s or summers?

Also do flat spots really happen in a day or 2? I find that crazy, but who knows. I get some shake as well, but fully intended to replace the tires ASAP from the get go. Just trying to figure out what tires don't shake and flat spot so fast.
Im on the oem all seasons and yes if my car sits two days or more and this is in a cooled garage in Florida, I get the flat spots. So yeah its pretty bad.
 

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Im on the oem all seasons and yes if my car sits two days or more and this is in a cooled garage in Florida, I get the flat spots. So yeah its pretty bad.
Hey! I'm In FL too lol, and we both got our cars nearly the same time. I also garage park it on the cold concrete. Good to know these things happen so quickly
 

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Hey! I'm In FL to lol, and we both got our cars nearly the same time. I also garage park it on the cold concrete. Good to know these things happen so quickly
I have had vettes before with the horrible run flats and I had a mustang GT as well with the Pzero's and they all did this. I knew it instantly the first morning I drove the car and it has a nasty vibration at 71mph, but then was gone after a few minutes of driving.

And for the record, I CANT believe the OP's dealer cant figure this out. They ordered a driveshaft??? Really?? Since when do driveshaft vibrations fix themselves after a few minutes of driving, but then come back?? Wow just goes to show that even the so-called experts are just there to get a paycheck. Took a random set of guys on the internet sight unseen to realize this was tire flat spotting.
 

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I have had vettes before with the horrible run flats and I had a mustang GT as well with the Pzero's and they all did this. I knew it instantly the first morning I drove the car and it has a nasty vibration at 71mph, but then was gone after a few minutes of driving.

And for the record, I CANT believe the OP's dealer cant figure this out. They ordered a driveshaft??? Really?? Since when do driveshaft vibrations fix themselves after a few minutes of driving, but then come back?? Wow just goes to show that even the so-called experts are just there to get a paycheck. Took a random set of guys on the internet sight unseen to realize this was tire flat spotting.
Sounds like they are just logging hours lol. First thing I saw was the bad blower and I was oh no! But then the driveshaft? I mean it's possible, just sounds strange and that it's doing the most complex things first, vs the easiest.
 

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2021 widebody Redeye Pitch Black.
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Flat spots all the way! Mine does it after sitting for a few days, no big deal, it corrects itself after a few miles. After sitting for a week or two it's worse. Soft tires do this easily.
 

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2020 Challenger Hellraisin Scat Pack.
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For those you who get this, are you on pirellis a/s or summers?

Also do flat spots really happen in a day or 2? I find that crazy, but who knows. I get some shake as well, but fully intended to replace the tires ASAP from the get go. Just trying to figure out what tires don't shake and flat spot so fast.
There can arise flat spots from the car sitting too long. To avoid this the factory inflates the tires to IIRC 45psi.

Once the car has been sold the tire pressures should be 32psi but check your car's door tag for proper inflation pressure.

With a number of cars with high performance Pirelli, Michelin, Continental and Bridgestone tires under some conditions the tires will over night or two have some signs of flat spotting.

This is normal. I found the problem is most likely when it gets hot during the day but then cools off quite a bit at night. If it stays hot all night long the tires don't cool down enough to develop a flat spot and if the day is not hot enough the tires do not get hot enough to deform slightly once the car is parked and even if it cools down.

I was about a mile or so from the freeway. Often by the time I got the freeway the tires had smoothed out. It was the rare event the tires took any freeway time to lose all the flat spotting but it happened. I can't recall the circumstances but it must have been a perfect combination of hot enough day time temperature and the tires getting plenty hot then after the car put away for the night the night time temperature dropping pretty fast and dropping quite a bit.

Really as long as the tires smooth out after a few minutes/miles (worst case) driving the situation is normal but harmless. I would be very reluctant to run the tires over the recommended door jam tire pressure. 50psi as someone suggested I think is above the max inflation pressure on the sidewall. This should not be exceeded and if you do want to experiment with tire pressures you should allow for the fact the tires will heat up and the tire pressure will go up by a few psi. Even with 32psi I have seen the tire pressures go to 36psi after some running in hot weather.

I would also be reluctant to replace the high performance tires with all season tires. While the all season tires probably won't flat spot they are in my experience lousy tires to fit on a high performance car. I would rather put up with just a bit of mild flat spotting that goes away in nearly no time than to live with lousy tires all the time.
 

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2021 Redeye Super Stock
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Sounds like they are just logging hours lol. First thing I saw was the bad blower and I was oh no! But then the driveshaft? I mean it's possible, just sounds strange and that it's doing the most complex things first, vs the easiest.
Not to high jack the thread, but Im jealous of the dealer service! If mine obviously had a bad blower, it would be hard to get the work done and covered for one. And two, having to trust them to not abuse my car and/or screw it up.
 

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The tires are junk. Michelin or Continental
 
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