Flat Spot

[marc1]

Last night while coming home in the dark, a deer ran out abruptly in front of me at 65MPH. I did a 4 wheel lock up (non-ABS car) for maybe 2 seconds then it was over (the deer was gone and I carried on). The car weighs about 3200 lbs and was fully loaded with passengers and the trunk was full of heavy stuff, so we were near the 4k mark I am sure. Sure enough... now at low speeds I have a thumping sound that is MPH related in frequency. These are Michelin X-Ice (probably the best winter tire I have ever used) however I was on dry asphalt when I locked up and they screamed low and hard for those 2 seconds or so. I was surprised tire lugs didn't rip out.

I can count on one hand the number of times I have locked my brakes in 30 years of driving so I don't have any experience with this issue. Will this, what I think is a flat spot probably on all four tires, smooth out with time as the tires wear naturally... or is that wishful thinking?

Thanks.

 

[CapriRacer]

First, you should look at the tires and see how bad they are. That's as good an indication as you are going to get of what you ought to do.

Second, they might get better, but probably not. This is very highly dependent on how good your alignment is. Mostly likely the flat spot is going to result in a series of spot wear downstream of the flat spot.

But what's your alternative? Replace the tires? Why not see if it gets worse? The only issue is that it may take several months for you to be sure - and by then winter tires will no longer be in stock

OTOH, if you can stand the vibration until April........

 

[zrxkawboy]

I once flat-spotted the two rear tires on my 67 Belvedere while avoiding a deer. I had to replace them. But, I understand that for you, it's four tires, and they're probably pretty spendy tires. Sorry to hear about that, but glad you avoided Bambi.

 

[marc1]

Originally Posted By: CapriRacer
First, you should look at the tires and see how bad they are.


So I can't see anything at all visually... but even a 1mm shave in one spot I might not catch with my eye? Not sure. Tires look fine though.

 

[marc1]

Originally Posted By: zrxkawboy
Sorry to hear about that, but glad you avoided Bambi.


Thanks I appreciate your comments and yeah I am happy I avoided the deer (that's the main thing)... even if it ruined $600 worth of tires. I will just live with it I think, they have about 85% tread left... so maybe 3 years?

I usually brake easier and don't panic but this thing appeared out of nowhere and ever since I came within $500 of writing off my nice Z71 a few years back when I hit a deer I am really gun shy of deer etc. now.

 

[Steve S]

I am sure there will be no problem if you just keep on using the tires.

 

[Steve S]

Deers suck.

 

[Carzzz]

Here is a way to cure flat spot
- inflat the tires to max pressure
- drive on highway for 10-15 miles
- deflat back to normal pressure

I guess this way can somewhat cure the flat spot!

 

[marc1]

Originally Posted By: Steve S
Deers suck.

Absolutely!

 

[marc1]

Originally Posted By: Carzzz
Here is a way to cure flat spot
- inflat the tires to max pressure
- drive on highway for 10-15 miles
- deflat back to normal pressure

I guess this way can somewhat cure the flat spot!


I think this works for flat spots from long periods of sitting... mine is probably ground off rubber in one spot, however I really appreciate your tip and I'll give it a try and let you know how it worked.

 

[Billbert]

You might call around to some of the independent tire shops and find one that has a tire trueing machine. They cut off a lot of rubber, but that beats a vibrating car.

 

[Dualie]

X2 on billberts comments

 

[ksJoe]

Here's an idea... The problem is, when rotating quickly the flat spot doesn't make good contact with the road. So what you need to do is a few full throttle smoking burnouts. Get the tires spinning fast enough that the flat spot doesn't have time to fall down to the pavement. That way, you only burn off the rest of the tire.

And if it doesn't work, at least you had some fun with tires you were going to replace anyway.

Oh wait a minute, I thought I was browsing the humor section. Nevermind.

 

[marc1]

Originally Posted By: ksJoe
Here's an idea... The problem is, when rotating quickly the flat spot doesn't make good contact with the road. So what you need to do is a few full throttle smoking burnouts. Get the tires spinning fast enough that the flat spot doesn't have time to fall down to the pavement. That way, you only burn off the rest of the tire.

And if it doesn't work, at least you had some fun with tires you were going to replace anyway.

Oh wait a minute, I thought I was browsing the humor section. Nevermind.
LOL! I thought about it actually... ;-)

 

[marc1]

Originally Posted By: Billbert
You might call around to some of the independent tire shops and find one that has a tire trueing machine. They cut off a lot of rubber, but that beats a vibrating car.
That's not a bad idea. I'll see how it turns out. Thanks.

 

[bluemax1]

Thought I'd add a few points here.

1) Usually, shops won't shave tires that have already been run. The tires pick up little stones and all sorts of grit and would dull or ruin the blades in short order.

2) The burnouts are your best bet, depending on how bad the flat spot is. You'll have to find a nice bit of clear asphalt (preferably an empty parking lot) and go for it.

It can be difficult to see a flat spot from looking at a static tire. The easiest way to see it is to have the wheel spinning, i.e. by jacking the car up in the air and spinning the wheels, or by mounting the wheel and tire on a wheel balancing machine and spinning it.


Max

 

[Rand]

I did that to some studded snow tires the second day I had them..

a Semi-truck was avoiding a crazy driver and almost side swiped me.

I was driving a '94 t-bird with a eaton m112 supercharger and 4.6L engine.

That car had alot of go.. but not much stop... The 2 back tires were done.. luckily the shop replaced them free. I went back there for tires 3 more times(paying) until they sold the shop and the new owners kept trying to sell me repairs I didnt need...

I'd just run the tires if its unbearable.. get new ones. or replace the pair that are the worse.. could be the front or back are much worse and only 2 need replaced.

 

[marc1]

Originally Posted By: Rand
I did that to some studded snow tires the second day I had them..


Yeah I am pretty annoyed (still) this was my second winter and such a beautiful set of tires, they handle like I am on rails over bad icy / snow covered roads.

It could be me... but I think it is getting worse (the thumping, I have another thousand plus miles on the tires since the deer incident)... however I am just going to live with it I have decided.

 

[ATS-V]

I'm sure it's only the front two that are flat spotted. If you rotate front to rear it should be less noticeable.

 

[marc1]

Originally Posted By: 97 GTP
I'm sure it's only the front two that are flat spotted. If you rotate front to rear it should be less noticeable.


You are probably right and I thought about that too... next winter they'll be swapped and I'll see. Good call.