chevygirl

iTrader: (69)

I need some advice. I am having trouble with outside tire wear on both front tires with less than 700 miles. Both outsides look scuffed. Alignment done on 2/18/09. Had the same problem before alignment. Everything is stock 1999 Z28 with Goodyear Eagle F1 275 40 17 tires.
Any advice

Here are my specs from 2/18/09
After alignment
Camber L 0.3 degrees R 0.1 degrees
Caster L 4.6 degrees R 4.4 degrees
Toe L -0.06 R -0.04

Let me know what you think.

JamRWS6

I had the same question and did some searching. Here are the stock specs:
Caster +3 degrees +/- .5 degree
Camber +1 degree +/- .5 degree
Toe in .15 degree +/- .5 degree

Looks like your camber is causing your fronts to wear on the outside. Don't take this as fact as I'm not expert on this and this is the first mention i've seen of specs.

Does your car feel like the steering is heavy? Looks like you have too much caster too.

Do you have any feathering on the tires as well? Looks like you have toe out by your specs. The stock settings are +.

chevygirl

iTrader: (69)

Yes the edges of the tread are feathering on the outside of the tire. I have an appointment in the morning and need to get this place to get it right. These are high dollar tires.
Only thing adjusted on 2/18/09 was the toe from -.23 to -.10
Had wear on the outside then to in the same places. Nothing has changed.
Need advice from you guys.

JamRWS6

Hopefully someone can chime in. If the feathering is really bad your tires are probably toast and won't be the same. Mine was aligned to stock specs (I don't know the exact specs on mine) and I also have the 275/40/17s and have 30K on my current set with no abnormal wear. Just a lot of highway miles.

99Bluz28

iTrader: (35)

Too much toe-in.
Also it wouldn't hurt to run a little - camber(-.1) if possible.
http://www.aa1car.com/library/tire_wear.htm

chevygirl

iTrader: (69)

Where should the toe be at?

chevygirl

iTrader: (69)

My tire looks like the feathering and camber.

99Bluz28

iTrader: (35)

Okay, I found my last alignment sheet.
For toe:
Front left .01*
Front right .01*
Total toe .02*

chevygirl

iTrader: (69)

Also I do not drive agressively and mostly highway miles.

99Bluz28

iTrader: (35)

FYI,
I have UMI front LCAs and G.W. UCA delum bushings, so my "toe" will change less than if you have stock front LCAs and UCAs with the rubber bushings when driving.
IMO,shoot for "0 toe" to 1/2 your current "toe" specs.

99Bluz28

iTrader: (35)

Here's the Spec. range I found for a 97-02 camaro:
Camber: -.1* to .9*
Caster: 4.3* to 5.3*
Toe: -.10* to .10*

chevygirl

iTrader: (69)

I see my specs are within the range but I know there needs to be an adjustment on mine because it is messing up my new tires fast.

I think I need to go for 0 toe and -.1 camber and maybe that will fix my problems.

If I can get the guy to actually do it. I am paying again so hopefully they will do it like I say as long as it is within gm specs.

z28bryan

iTrader: (7)

Stock camber is too positive. My tires used to wear out on the outside too. Try to even get around -.5 if possible. I also have had 0 toe for a while. 0 toe is very safe to drive on and doesn't feel too twitchy. Hell -1.5 is wearing pretty even for me. I've driven on this from 245 width snow tires to 315 race tires on all 4's.

jclz28

With the stock specs you will wear out the outside edge of your tires. You really need to go more negative on the Camber (-.5 deg if you corner gently, -1 deg or more if you are aggressive in corners). Go for at least 4 deg of Caster (this is what recenters your wheel, more caster and your car will straighten itself out on the highway). Toe in should be 1/16 to .125 inch for a daily driver. Yes, it does increase outer tire wear, but it effects high speed stability. You really want to have the least amount of real toe in during driving that you can without going to toe out. Toe out makes a car very reactive to steering, and while this is ok for autocross and cornering turn-in, it will make you think the car is very 'darty', to the point where it is tiring to keep straight on the highway.

Realize that these numbers are for a daily driver, and one with a suspension in pretty good shape. Worn tie rod ends wont let you hold toe in, worn ball joints will mess up both camber and caster.

chevygirl

iTrader: (69)

This place I am using has the Hunter Hawkeye alignment machine and is a chevy dealer.
I just want to make sure where he puts it at it does wear the tires evenly. I have had a time with my new tires anyway and don't want to go through it again anytime soon.
They have already inspected my front end twice since Feb. and said nothing was worn or a problem. I just don't understand why he set my alignment like he did when he knew I had bad outer tire wear and told him I wanted to make sure it would wear evenly and how expensive these tires were. I will see what I can get him to do.

Do you think -.5 camber is too much since that is off the limits on the stock specs?
I have read 0 toe was good on these cars and if I already have a wear pattern after 700 miles just like before real adjustments need to be made to make a real change.

99Bluz28

iTrader: (35)

-.5* isn't too much at all.

I would talk to the service manager, if the alignment they did on your car is causing uneven tire wear they should re-align it for free!
If their alignment guy can't set the alignment where/how you want it go elsewhere.

chevygirl

iTrader: (69)

Well I will see what I can make them do at my appointment in the morning. Just looking at my new tire scuffed up on the outside really makes me mad. I didn't have an specs when I went I just trusted that I could show them the problems and they could fix it. He said it would.

leadfoot4

iTrader: (1)

MINUS values on "toe-in" are ACTUALLY "toe-out" !!


I just aligned my '96 Z-28 a couple weeks ago, also on a Hunter Hawk-Eye machine. The settings I used are:

Camber...."zero", both sides
Caster.... 5 degrees positive, left side; 5.5 degrees right side;
Toe....... .04 degrees both sides



Specs from my '96 factory shop manual (page 3A-6):

Caster........... 5 degrees, +/- 0.5 degrees;
Cross Caster... "o", +/-0.7 degrees;
Camber......... 0.4 degrees; +/- 0.5 degrees;
Cross Camber.. "0"; +/- 0.7 degrees;
Individual Toe.. "0"; +/- 0.1 degrees;
Total Toe........ "o"; +/- 0.2 degrees.

vjo90rs8

iTrader: (9)

get away from those stock specs
I have even tire wear and am running
camber: -0.7*
caster: +5.5*
and a bit of toe in

chevygirl

iTrader: (69)

Okay here is how it came out. If he brought my camber to -.5 it brought the caster down to 3.6 so I had to go with -0.1 camber to get 4.1 caster. He tried to get 0 on the toe but could not get 0 toe to stay so here is as close as we could get after 2 hours on the machine (he wasn't happy about that either)
After alignment See above for before
Camber L -0.1 R -0.1
Caster L 4.5 R 4.1
Toe L 0.03 R 0.02 Total toe 0.05

That is as close to you all specs that I could get. I am running totally stock. My main concern is even tire wear. I noticed it doesn't feel as tight on the highway speeds. It wonders just a bit more than it did. The dealership was pretty much not happy with me when I left because I took so much of their time. They had no problem charging me the 60.00 again after 3 months.

Any comments welcome.