Just got out of the car, and noticed a heavy coat of what looks to be black tire dust on the front fender of the car. I have just recently got the car back on the road after a front end rebuild, including a front end alignment which seems to be great. Since then I have only put a few hundred miles on the car, so seems like a LOT of dust for such a short time driving it. This may have been like this before and I just didnt notice it, but im a little hyper aware right now since the rebuild.

Does this look normal or am I munching tires big time?? Its on both front fenders in basically the same place.

 

This is not normal. Measure the thread depth on each tire.
Also rub your hands on the threads both the forward rotation and reverse. Does it feel smooth or do you feel a feathered feeling. Compare left edge vs right edge vs center.

I think you may have an alignment toe problem.

Do you have the print out of the alignment settings.

 

I agree .. I always had some, but I do a lot of highway driving.... I added the splash guards to keep some off the car and side pipes .... It looks like you have more than I do ....Are these new tires? Maybe a softer compound ?

 

Did you by chance change the rotors and pads?? I find while new pads are bedding I get a lot of dust.

 

Tires are not new. They are a little old actually. Some signs of dry rot if that gives any clues.

Rotors and pads have not been changed.

Here are the alignment settings

Is there anything obvious that would reveal I have a toe issue without having to take it back in to an alignment shop?

Ive driven a bunch of highway miles in the past week or so (around 400-500 miles) if that sheds any light.

Ill check for the feathering now.

 

This is a very poor alignment.

1. that is about 1/4" toe in ( I like 0.05 degree's / wheel ) 1/16" toe
2. rear toe is also out. Reads as toe out when it should be toe in.
3. trust angle is also very poor. (poor rear wheel toe alignment)
4. camber settings for best highway/street driving should be 0
I like max toe 1/8" front usually set to 1/16" front 1/8 rear with almost 0-0.01 thrust angle.

Use this as a guide.
http://tech.corvettecentral.com/2011...ignment-specs/

While they might be with-in specs but they should be able to do better.

Generaly I would not be happy with those settings.

 

Thats a total bummer.

I looked for quite some time before settling on the shop that did this alignment. And it wasnt cheap. It was $125 for the front end only.

Which by the way, I only asked him for a front end alignment. He did tell me once he was finished that he made a small adjustment to the back, but sounded like he didnt do much to it since I asked (and was paying for) a front end only alignment.

He did say something about hitting the maximum threshold on something, but I cant recall what it was.

The only instruction I gave him was following Borgeson's 3-4 degree castor recommendation. Other than that, I asked him to align to factory specs.

Thanks for that guide link. Never saw that before. Assumed whatever he needed was in his computer program.

Judging solely on how the car feels and drives, its a noticeable improvement from where it was when I brought it in. It drove like crap before. Felt like I was standing on a basketball when I was driving it. Bump steer was significant and was very darty.

I still feel a little bit of bump steer on less than perfect roads, but I figured that was just how these cars handle.

Is this a big enough problem that I should get it realigned immediately?

Thanks for the help on this.

 

First thing is to check out the condition of the rear suspension.
The trailing arm bushings, strut rod bushing etc.
A simple test you can do is see how much effort to takes to rotate the wheel in the 6 & 12 oclock position with the wheels off the ground. 2 things you will notice. How much play you have in the yokes and how easy the trailing arms move at the piviot point in the frame. In a perfect world there should be very little movement with little effort.

Also check the conditions of the shims. If the bushing have never been replaced and odd's are the shims and piviot bolts have rusted to the frame and may need to be cut out and replaced. Most alignment shops only like to do rear camber adjustments on older corvette's because its a lot of work to adjust the rear toe. Piviot bolt / shims cannot be rusted to the frame to adjust. Most shops also dont have any shims.

If you find the rear loose then this needs to be fixed. The good thing is that you have older tires on the car, so its not a big lose if the alignment isn't perfect right now.

If the rear is nice and tight then I would look at fixing the alignment.
(assuming they can adjust the rear toe / shims are ok)

As it sits now you will have premature tire wear and poor handling. Dont replace your tires until all alignment issues are resolved.

Also dont spend any more money changing the alignment until all suspension issues are checked / fixed.

 

As you alluded to in your initial post, the dust may have been created before your alignment. A simple test would be to wash the car and see if the dust returns.

 

I will be inspecting the rear suspension very soon. Im sure the bushings are original and rotted.

I did clean the car off and the dust is forming again.

 

You will need to check and trailing arm bushing (shims and pivot bolts), strut rod busings, the spring for sag, side yoke play, rear bearing play. Once this is all in working order then I would get the alignment fixed, and once it drives proper then replace the tires as required.

There is a lot of info on how to check this out on this forum.

good luck and hope this work out with little expense.

 

Wanted to follow up on this thread (I hate it when I come across threads that remain unresolved).

So the excessive tire wear was related to my f*#$%^g shims falling out after the crappy alignment I got. It took a while to discover it because the shims were on the passenger side covered by the air ducting.

Anyway, the car was realigned. Curious if you guys think this alignment looks better than the one I posted earlier in the thread.

 

Front looks fine. Could use more camber.

I can also tell they have not done the rear toe. One side is toe in and the other toe out.
You also have positive camber in the back.

 

For me the front has too much toe. double what i would ever set.

But check how it wears.

The rear is a mess. Wrong camber and rear right tire is toe out when it should be toe in. Thrust angle is very high. Best near 0. I would not except the rear alignment. I think all they did in the rear was fill the pockets with shim's and call it a day.