New rear tires (scary story)
 

I knew I was going to need tires soon. I could see the wear bars beginning to show. Not bad, but getting there. Then I started to hear an odd noise from the rear of my car. The ride didn't seem very smooth either.

Now keep in mind most of my driving is highway miles (70+ mph)

I got down low and looked at the tires and could see on the passenger side a worn spot.
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Well damn it. No procrastinating, time for the purchase. At the shop to get them put on, I noticed that they were worse than that!

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Awww hell. I feel foolish. How could I have let them get that bad?!

Well wait. It gets worse.

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Putting my phone inside the tire, still on the car, but on the lift.

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Thank you lord for sending the guardian angel that was looking after me. I can't believe that I didn't have a blowout.

Go easy on me people. I'm plenty angry with myself.

make sure to get your alignment done at least once a year !http://986forum.com/forums/uploads01...1437269639.jpg

I monitor my tires. So far, so good!

As I get up off the couch to go check my tires......

Holy corded tire Batman!

Same thing happened to me a little over a year ago

I thought that looked familiar!
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Me, a couple of months ago. The tires looked fine, until I crawled under the car to check the condition of the ball joint boots. That was a bit of a shock, the wear pattern on the rear tires is deceiving. Got a 4-wheel alignment with the new tires.
Glad you didn't experience a failure on the highway!

Great reminder to us all. Thanks for the courage to make this post. Off to crawl under mine then a night sleep

Great post. I have a very distinct vibration @ 35-40 and 65-70. Brought it in for balance. That inside edge is right at tread bars and between that and an alignment from replacing a trailing arm it needs an alignment and rears this week.

What does a proper alignment make the rears sit like? As far in on that inner edge? Should we be telling the alignment guy anything?

It is post like this that..... saves lives. Nice job.

Thanks for the courage to post about your own mistakes, it's pretty clear that we all make them. A good reminder to the rest of us here!

And I thought I rolled with good guardian angels.

Common wisdom is to get as much negative camber OUT of the rear wheels. It will always be somewhat negative because the nature of the stock suspension.

Second, and probably more important, get the rear toe as close to 0 deg. as possible. Most people think the inside wear is caused by negative camber but its usually because of too much toe.

The rear will be much more lively at 0 toe, which most people like because the car rotates easier, some people find it "twitchy".

I learned the same lesson (the same way) in 1990 on my 71' Triumph TR-6. Outer edges of tires looked fine, inside edge was falling apart. Glad that you noticed it before something serious happened!

For a street car, I'd suggest staying with the stock alignment spec's (which can still result in uneven tire wear). Yes, heavy inside wear can be somewhat aligned out, but it will be as a trade-off for some other non-preferred condition (like poor or even scary handling).

The take away here is to check the entire width of a tire.

My standard is 3 measurements across the tread and spin the wheel with your hand resting on the tread to feel any irregularities.

Most auto shops sell a really cheap measurement device that allows you to push a plunger into the gap and then do a simple readout.