85IrocZ-28

My front tires are wearing out faster than the rears. It has always been this way. The outer edges seem to wear out fast, and my alignment is just fine.

I was thinking of lowering the car one inch, or changing the alignment so that the tires tilt in on the top just a little.

Has anyone else had this problem, or know how to fix it...or should I just lower it in hopes the change in geometry will help with the tire wear...

Tobias05

what tire pressure you running the fronts at? do you rotate?

sofakingdom

iTrader: (1)

What EXACTLY does that mean? (specs)

If it's set up at stock specs, it will eat tires like they're free.

The best way to align these cars, for street use, is to about 4°/4.5° positive caster, -1°/-1.5° camber (those are given as L/R), and about 1/32" toe-in. The factory "specs" have positive camber, which GUARANTEES to chew off the outside edge in a few hundred miles.

Weak struts will aggravate it. If yours haven't been changed lately, try a set. Makes the car ride A WHOLE LOT better at the same time.

Doesn't matter if the car is lowered or not. In fact, indiscriminately lowering the car without making the appropriate changes to go along with it, can easily make it worse.

85IrocZ-28

I run the tires at 33-35 PSI, and do not rotate. I have factory IROC rims. I do have the front tires pancaked so that I wear both edges out before replacing the tires. The struts have about 15k on them.

As far as the alignment goes, I have always used factory specs. I thought that was the best. How many people are running different than factory as suggested?

sofakingdom

iTrader: (1)

Pretty much everybody that knows what they're doing.

Visit the FAQ pages on this site, such as this one. https://www.thirdgen.org/suggested-front-end-alignment You'll see pretty similar ones posted there too; although whoever wrote those up, didn't call for caster or camber split, which if you set both sides the same, the car will always seem to "drift" or even "pull" right due to the crown in the road.

Yeah everybody always thinks that the factory spec for everything is "best". Seems reasonable to think that, on the surface. On the other hand, why do we ever mod ANYTHING? Because the factory spec IS NOT "best", in our view. Maybe the factory alignment spec is "best" in some way; maybe the cars fit on the rail carrier best as they left the plant with the wheels set like that. I have no idea. They have ALL SORTS of concerns that we out here in meatspace DON'T, and can't even get a glimpse of. Maybe they just thought that if a brand-new car was set up like that, then as the crappy soft springs they put in them sagged, they would "come in" to the right values. I just don't know. All I know is, their spec isn't "best" for tire wear, handling, steering "feel", or anything else that's important to ME.

Sonix

iTrader: (1)

sofa, can you edit your first post? You listed a spec for camber, then for camber. I know one is camber, but it's not obvious to some which is which (including me)

85IROC - i'm using spec's similar to what was listed in the link sofa mentioned. There's a lot to improve on, vs the factory settings. Also, the shop who laser aligned my car couldn't get it all the way to those specs, not enough travel in the strut adjustment slots. If you've got some time, elongate the holes a tad with a die grinder before you bring in the car.

sofakingdom

iTrader: (1)

I guess my one functionating brain cell must have got a cramp right then.

Conider it done. Thanks for pointing that out!!

85IrocZ-28

Your info is GREAT! Thanks for setting me in the right direction. I am going to take these numbers with me when I get it aligned.

As far as grinding the holes...I believe you are talking about the three that are on the top of the strut tower...So I would want to elongate them so that they can be adjusted further inward towards the motor? Please correct me if I am wrong.

slow_90firebird

I used to work at firestone, and for every alignment, they always just adjusted the tie-rods.

I never have had the car aligned. I want to wait till I get new tires, and possibly lower the car. But I will keep those specs in mind.

Sonix

iTrader: (1)

Yes, inwards.
Tie rods adjust your toe settings, for caster and camber you need to adjust the strut mounts.

sofakingdom

iTrader: (1)

Inwards, for camber; and rearwards, for caster. Most cars don't have any trouble reaching the right camber, but may not allow the top of the strut to go far enough back to get that much caster.

slow_90firebird

yeah, I understand. But I mean, at firestone they JUST adjusted the tie rods. On every car. Even if the other values were still in the red!

RBob

iTrader: (1)

'raise hand'

I realize that you have a bunch of replies since you asked this. But it really is that way. Even on a stock Camaro driven easy the outside edges wear. I used to rotate a lot to even out the wear. Finally started doing my own alignments and giving it about 1/2 deg of negative camber.

The amount of neg camber depends upon how the vehicle is driven. IE: drive car, look at tires, adjust as required.

Even mostly highway had the outside edges wearing. Has to do with the zero (0) camber gain while turning, and body roll creating positive camber. All in the suspension geometry.

RBob.

Lonnie P

My car likes a lot of front tire pressure.... I run 42# in the front & leave the rear at 30#, it seems to work well for me. It still wears the front inner & outer edges faster than the centers, but helped both the handling & tire wear.

85IrocZ-28

When I pull into or out of a parking spot, it seems to catch, like since the tires are aimed slightly different, that the car follows the path of the drivers tire, then the passenger tire, then the drivers....and so on. I know this is adding to the wear as the tires are tilted on sharp turns. Has anyone else experienced this, and did changing alignment specs fix it?

slow_90firebird

My car plows a little too in sharp corners in a parking lot. I never guessed why - I just figured cause it's old and tired. It's worse on a sandy surface too.

Sonix

iTrader: (1)

That's funny, my buddies '85 V6 camaro did that back in the day, WEIRDEST sensation ever. Taking a sharp turn in a parking lot felt like it was 'tripping over itself' sort of. Strange. That could definitely be from positive camber, although I never did find out. My car kinda did it too.

85IrocZ-28

Yeah, it is a wierd feeling. It is terrible on ice, and this is my DD in Utah. No fun. I will look very carefully at the camber settings to make sure I like what they have done. I plan on going back into the shop to watch them do the alignment and make all of the changes as needed.

Thanks for all of your help.

joshh44

mine is doing the same. if i back out of the drive way and turn. makes a terrible grinding rubbing type of sound. sounds to terrible!! makes me grind my teeth hearing that noise. but thats at like full turn.

85IrocZ-28

Yeah, I guess there are many of us that are living with the same problem.

ezstriper

If the tires are wearing on the outer edges and tire pressure kept correct, then the alingment is not fine ! either to much positive camber or toed in to much, many alignment shops could not align a tricicle !!find someone who knowa what they are doing....did it for 17 years, Rob

stage20

iTrader: (3)

https://www.thirdgen.org/suggested-front-end-alignment
i am almost confused by that chart.
i think it needs to be put in a dropped pattern to seperate the different specs from street to race, etc.
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https://www.thirdgen.org/forums/atta...rite-specs.jpg
found that.
sweet.

85IrocZ-28

The problem is that the alignment shops use specs that are no where near what is listed in that article. After having the camber changed, I don't have the binding grabbing issue when turning sharp into or out of a parking spot.

It also rides better and handles much better in the corners. I will never let an alignment shop do their own thing again. The owner didn't know what to think of the numbers after I walked back in the office to pay. One of the shop supervisors came in while the worker was aligning my car to see what was taking so long. I told him that we were doing it right, not just a simple toe adjustment and out the door...If this wasn't a DD, I would just do it myself in the future. It is right where I want it now though.

I just thought the alignment was fine because it was always set to the specs each tire shop had. I just didn't know that their specs were so off where it really should be.

compuwiz1937

iTrader: (17)

85IrocZ - were they able to get your caster at those specs sofakingdom listed? My car is currently at 4.9* left and 5.2* right, and I don't see how there is enough adjustment to get it to 4* and 4.5*.

vetteman46

Try lubing the turn stops

Guest

I just read this. there is so much lacking info here and a bit of misguided suggestions. Some good suggestions also but those posts just talk about going to a better alignment shop.

First of all, a good alignment shop will INSPECT all suspension componants for "wear" and "slop" before they just try and adjust things then take your money and send you on your way. A bad shop will just set things to factory spec with static loading on the suspension (meaning the car is just sitting there not moving) and take your money. you come back and complain and they just tell you the printoput reads to factory specs so its not their fault- TRUE- but they should tell you beforehand of worn parts and the affect of dynamic loading on the alignment and tire setback from road force when moving.

What is affected with dynamic loading? Everything. One bad part will cause a problem. Balljoints, tierods, strutmounts, tire size varience (unwanted stagger), control arm bushings, pitman arm, etc... All of these factors will show fine in a static alignment, but cause probelms in dynamic loading. So "yes" your alignment is probably fine, your suspension is most likely the problem. Further adjusting the alignment will not help.


Also- Once everything is checked out and up to par- NEVER (I will repeat again) NEVER go as high as 1 to 1.5* negative camber on a daily driver. You WILL get inside tire wear. try to keep it at .5 to 1*neg range. The toe should also not be at 1/32 for anything other than a drag car and progressing up to positive toe for a short course autox car that sees low racing speeds. Set the toe at 3/32 for a street car that sees freeway driving speeds otherwise you will have a steering wheel that is a handful.

Caster? Basically, the more positive caster you put into the car, the more effort to turn into the corner, but the easier the effort coming out of the corner (in essence, the steering wheel will straighten itself easier if released from a turn.) High caster will cause bumpsteer because the suspension travel path not only goes upward but now more backward as well and this strins the matching angles of the tierods path to shorten the toe and cause darting side to side on road inperfections

Suggestions on alignments are really based on tire size and upgrades done to the car. I had a camaro about as built as you would ever see and I ran 5/5.5 caster, -0.8 camber, and 1/16 toe- BUT!!!! I also induces roll understeer in the rear of the vehicle when dynamically stressed. To run that caster, I had a very limited suspension travel on a very lightweight car with all custom provisions welded and bolted in for proper setup.

Sonix

iTrader: (1)

Huh, someone with a bunch of suspension knowledge, who knows how to string together a coherent sentence, explain his advice, and even (gasp) uses correct punctuation?!?
Who is this freak of nature? Welcome back guy

RacerX13

Glad to see you're back-your expertise has been sorely missed.

Guest

Thnaks guys, but I was trying to stay incognito. I guess not though....

Sad to say, I do not have a Camaro anymore due to personal issues. I actually came onto this board with talk about a local event gatrhering this weekend between a few local So Cal Camaro guys on here and a local Corvette club.

85IrocZ-28

Thanks for the additional info. Here are my alignment numbers right now...

Camber
Left= -1 degree
Right= -1 degree

Caster
Left= 2.3 degrees
Right= 2.6 degrees

Toe
Left= .18 degrees
Right= .17 degrees

It rides very well, and corners SO much better than it did before. It is amazing how much the ride has changed. It may need a bit more toe in, I am not sure how to covert the toe in degrees to an inch measurement. I may just adjust this on my own later if I don't like the way it feels.

I know that it is good to find a shop that knows what they are doing...but I have had multiple shops align it in the past, and every one of them used the crappy factory specs. this shope would have as well had I not been there to tell them what I wanted. I don't know of any shops that would have done this correctly without someone there watching their every move.
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I had to give up some caster to get the camber I wanted. As camber was more important to me for tire wear and stance, I didn't go nearly as high on the camber as listed. We'll see how these tires wear. I will just keep adjusting a little each time from here on out to see what rides and wears the best. This is my DD, so I go through a set of tires every 2 years.

zride91

Just a note to add:

I read also that people were experiencing the same symptoms due mostly to the age of the car (and mostly front coil springs). The front springs would get old and you would actually change your ride height over time (goes the same when you put in lowering springs). The geometry of the steering system changes with the ride height causing the front wheels to turn at different rates and "drag" while turning. This can be fixed by replacing the front coil springs with new OE ones, or getting a bump steer kit as below (other manufacturers make it as well).

http://www.spohn.net/?action=product&pid=1739

If all your alignment work did not fix your problem, this would be my next step...

Guest

Nope, that will not fix his problem. If springs sagged for what ever reason- and I have never had a spring sag issue in all the years I have had coils on cars- thats kindof a myth to the extend most claim ill effects) the car is simply aligned to the new "SLIGHTLY" lower eide height than factory. Not anywhere near enough to warrant a bumpsteer kit and people just wasting more money trowing new aftermarket addons on a bandaid fix- instead of fixing the root of the problems link worn componants.